89-B

1. P. V. Giannoudis, C. C. Tzioupis, H.-C. Pape, and C. S. Roberts. Percutaneous fixation of the pelvic ring: AN UPDATE. J Bone Joint Surg Br 89-B: 145-154.

2. M. Saudan, P. Saudan, T. Perneger, N. Riand, A. Keller, and P. Hoffmeyer.

Celecoxib versus ibuprofen in the prevention of heterotopic ossification following total hip replacement: A PROSPECTIVE RANDOMISED TRIAL. J Bone Joint Surg Br 89-B:

155-159.

3. R. Blomfeldt, H. Törnkvist, K. Eriksson, A. Söderqvist, S. Ponzer, and J.

Tidermark. A randomised controlled trial comparing bipolar hemiarthroplasty with total hip replacement for displaced intracapsular fractures of the femoral neck in elderly patients. J Bone Joint Surg Br 89-B: 160-165.

4. A. R. Chitre, M. J. Fehily, and D. J. Bamford. Total hip replacement after intra-articular injection of local anaesthetic and steroid. J Bone Joint Surg Br 89-B:

166-168.

5. J. Daniel, H. Ziaee, C. Pradhan, P. B. Pynsent, and D. J. W. McMinn. Blood and urine metal ion levels in young and active patients after Birmingham hip resurfacing arthroplasty: FOUR-YEAR RESULTS OF A PROSPECTIVE LONGITUDINAL STUDY.

J Bone Joint Surg Br 89-B: 169-173.

6. Y.-H. Kim, S.-H. Yoon, and J.-S. Kim. Changes in the bone mineral density in the acetabulum and proximal femur after cementless total hip replacement:

ALUMINA-ON-ALUMINA VERSUS ALUMINA-ON-POLYETHYLENE ARTICULATION.


7. S. Koëter, M. J. F. Diks, P. G. Anderson, and A. B. Wymenga. A modified tibial tubercle osteotomy for patellar maltracking: RESULTS AT TWO YEARS. J Bone Joint

Surg Br 89-B: 180-185.

8. E. C. Rodriguez-Merchan. Total knee replacement in haemophilic arthropathy. J

Bone Joint Surg Br 89-B: 186-188.

9. J. C. Levy, N. Virani, D. Pupello, and M. Frankle. Use of the reverse shoulder prosthesis for the treatment of failed hemiarthroplasty in patients with glenohumeral arthritis and rotator cuff deficiency. J Bone Joint Surg Br 89-B: 189-195.

10. S. Veitch, S. M. Blake, and H. David. Proximal scaphoid rib graft arthroplasty. J


11. A. P. Arya, R. Kulshreshtha, G. K. Kakarala, R. Singh, and J. P. Compson.

Visualisation of the pisotriquetral joint through standard portals for arthroscopy of the wrist: A CLINICAL AND ANATOMICAL STUDY. J Bone Joint Surg Br 89-B: 202-205.

12. S. Houshian, C. Chikkamuniyappa, and H. Schroeder. Gradual joint distraction of post-traumatic flexion contracture of the proximal interphalangeal joint by a mini-external fixator. J Bone Joint Surg Br 89-B: 206-209.

13. J. S. Lee, K. P. Moon, S. J. Kim, and K. T. Suh. Posterior lumbar interbody fusion and posterior instrumentation in the surgical management of lumbar tuberculous spondylitis. J Bone Joint Surg Br 89-B: 210-214.

14. A. H. Krieg, and F. Hefti. Reconstruction with non-vascularised fibular grafts after resection of bone tumours. J Bone Joint Surg Br 89-B: 215-221.

15. H. S. Cho, J. H. Oh, H.-S. Kim, H. G. Kang, and S. H. Lee. Unicameral bone cysts:

A COMPARISON OF INJECTION OF STEROID AND GRAFTING WITH

AUTOLOGOUS BONE MARROW. J Bone Joint Surg Br 89-B: 222-226.

16. R. Maheshwari, H. Sharma, and R. D. D. Duncan. Metacarpophalangeal joint dislocation of the thumb in children. J Bone Joint Surg Br 89-B: 227-229.

17. J. Nakamura, M. Kamegaya, T. Saisu, M. Someya, W. Koizumi, and H. Moriya.

Treatment for developmental dysplasia of the hip using the Pavlik harness:

LONG-TERM RESULTS. J Bone Joint Surg Br 89-B: 230-235.

18. R. C. I. van Geenen, and P. P. Besselaar. Outcome after corrective osteotomy for malunited fractures of the forearm sustained in childhood. J Bone Joint Surg Br 89-B:

236-239.

19. R. Lamdan, A. Sadun, and M. Y. Shamir. Near-fatal air embolus during arthrography of the hip in a baby aged four months. J Bone Joint Surg Br 89-B:

240-241.

20. H. S. Uppal, S. E. Gwilym, E. J. P. Crawfurd, and R. Birch. Sciatic nerve injury caused by pre-operative intraneural injection of local anaesthetic during total hip replacement. J Bone Joint Surg Br 89-B: 242-243.

21. R. A. Haene, and M. Loeffler. Hair tourniquet syndrome in an infant. J Bone Joint

Surg Br 89-B: 244-245.

22. S. Funahashi, A. Nagano, M. Sano, H. Ogihara, and T. Omura. Restoration of shoulder function and elbow flexion by nerve transfer for poliomyelitis-like paralysis caused by enterovirus 71 infection. J Bone Joint Surg Br 89-B: 246-248.

23. G. Petsatodis, P. D. Symeonidis, D. Karataglis, and J. Pournaras. Multifocal

Proteus mirabilis osteomyelitis requiring bilateral amputation in an HIV-positive patient.


24. E. H. Seel, and E. M. Davies. A biomechanical comparison of kyphoplasty using a balloon bone tamp versus an expandable polymer bone tamp in a deer spine model. J


25. I. Nagura, H. Fujioka, T. Kokubu, T. Makino, Y. Sumi, and M. Kurosaka. Repair of osteochondral defects with a new porous synthetic polymer scaffold. J Bone Joint

Surg Br 89-B: 258-264.

26. J. Ristiniemi, T. Flinkkilä, P. Hyvönen, M. Lakovaara, H. Pakarinen, and P.

Jalovaara. RhBMP-7 accelerates the healing in distal tibial fractures treated by external fixation. J Bone Joint Surg Br 89-B: 265-272.

27. G. S. J. Chuter, D. J. Cloke, A. Mahomed, P. F. Partington, and S. M. Green. Wear analysis of failed acetabular polyethylene: A COMPARISON OF ANALYTICAL

METHODS. J Bone Joint Surg Br 89-B: 273-279.

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Abstract 1 of 27

Percutaneous fixation of the pelvic ring

AN UPDATE

P. V. Giannoudis, BSc, MB, MD, EEC(Orth), Professor1; C. C. Tzioupis, MD, Trauma

Fellow1; H.-C. Pape, MD, Professor2; and C. S. Roberts, MD, Professor3

1 Department of Orthopaedic and Trauma Surgery, St James’s University Hospital,

Beckett Street, Leeds LS9 7TF, UK.

2 Division Chief of Traumatology, Department of Orthopaedic Surgery, Pittsburgh

General Hospital, Suite 911, Kaufmann Med. Building, 3471 Fifth Avenue, Pittsburgh,

Pennsylvania, 15213, USA.

3 Department of Orthopaedic Surgery, University of Louisville School of Medicine,

ACB, Third Floor Bridge, HSC 234, Louisville, Kentucky, 40292, USA.

Correspondence should be sent to Professor P. V. Giannoudis; e-mail:

Pgiannoudi@aol.com

With the development of systems of trauma care the management of pelvic disruption has evolved and has become increasingly refined. The goal is to achieve an anatomical reduction and stable fixation of the fracture. This requires adequate visualisation for reduction of the fracture and the placement of fixation. Despite the advances in surgical approach and technique, the functional outcomes do not always produce the desired result. New methods of percutaneous treatment in conjunction with innovative computer-based imaging have evolved in an attempt to overcome the existing difficulties. This paper presents an overview of the technical aspects of percutaneous surgery of the pelvis and acetabulum.

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Celecoxib versus ibuprofen in the prevention of heterotopic ossification following total hip replacement

A PROSPECTIVE RANDOMISED TRIAL

M. Saudan, MD, Orthopaedic Surgeon1; P. Saudan, MD, Physician2; T. Perneger,

PhD, Professor3; N. Riand, MD, Orthopaedic Surgeon1; A. Keller, MD, Physician4; and P. Hoffmeyer, MD, Professor1

1 Division of Orthopaedic Surgery

2 Division of Nephrology

3 Quality of Care Unit

4 Department of Radiology, University Hospitals of Geneva, Rue Micheli-du-Crest 24,

CH-

1211, Genèva 14, Switzerland.

Correspondence should be sent to Dr M. Saudan; e-mail: marc.saudan@hcuge.ch

We examined whether a selective cyclooxygenase-2 (COX-2) inhibitor (celecoxib) was as effective as a non-selective inhibitor (ibuprofen) for the prevention of heterotopic ossification following total hip replacement. A total of 250 patients were randomised to receive celecoxib (200 mg b/d) or ibuprofen (400 mg t.d.s) for ten days after surgery. Anteroposterior radiographs of the pelvis were examined for heterotopic ossification three months after surgery. Of the 250 patients, 240 were available for assessment. Heterotopic ossification was more common in the ibuprofen group (none

40.7% (50), Brooker class I 46.3% (57), classes II and III 13.0% (16)) than in the celecoxib group (none 59.0% (69), Brooker class I 35.9% (42), classes II and III 5.1%

(6), p = 0.002). Celecoxib was more effective than ibuprofen in preventing heterotopic bone formation after total hip replacement.

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A randomised controlled trial comparing bipolar hemiarthroplasty with total hip replacement for displaced intracapsular fractures of the femoral neck in elderly patients

R. Blomfeldt, MD, Consultant Orthopaedic Surgeon1; H. Törnkvist, MD, PhD,

Consultant Orthopaedic Surgeon1; K. Eriksson, MD, PhD, Consultant Orthopaedic

Surgeon1; A. Söderqvist, RN, Research Nurse1; S. Ponzer, MD, PhD, Consultant

Orthopaedic Surgeon1; and J. Tidermark, MD, PhD, Consultant Orthopaedic

Surgeon1

1 Department of Orthopedics Karoli nska Institutet, Stockholm Söder Hospital,

Stockholm S-11883, Sweden.

Correspondence should be sent to Mr R. Blomfeldt; e-mail: richard.blomfeldt@sodersjukh uset.se

The best treatment for the active and lucid elderly patient with a displaced intracapsular fracture of the femoral neck is still controversial. Randomised controlled trials have shown that a primary total hip replacement is superior to internal fixation as regards the need for secondary surgery, hip function and health-related quality of life.

Despite good results achieved with total hip replacement in this group, most orthopaedic surgeons still advocate hemiarthroplasty for this injury. We studied 120 patients with a mean age of 81 years (70 to 90) with an acute displaced intracapsular fracture of the femoral neck. They were randomly allocated to be treated with either a bipolar hemiarthroplasty or total hip replacement. Outcome measurements included peri-operative data, general and hip-specific complications, hip function and health-related quality of life. The patients were reviewed at four and 12 months.

The duration of surgery was longer in the total hip replacement group (102 minutes

(70 to 151)) versus 78 minutes (43 to 131) (p < 0.001), and the intra-operative blood loss was increased 460 ml (100 to 1100) versus 320 ml (50 to 850) (p < 0.001), but there were no differences between the groups regarding any complications or mortality. There were no dislocations in either group. Hip function measured by the

Harris hip score was significantly better in the total hip replacement group at both follow-up periods (p = 0.011 and p < 0.001, respectively). The health-related quality of life measure was in favour of the total hip replacement group but did not reach statistical significance (p = 0.818 at four months and p = 0.636 at 12 months).

These results indicate that a total hip replacement provides better function than a bipolar hemiarthroplasty as soon as one year post-operatively, without increasing the complication rate. We recommend total hip replacement as the primary treatment for this group of patients.

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Total hip replacement after intra-articular injection of local anaesthetic and steroid

A. R. Chitre, MBChB, MRCS, Senior House Officer1; M. J. Fehily, FRCS(Tr & Orth),

Hip Fellow2; and D. J. Bamford, FRCS, FRCS(Orth), Consultant Orthopaedic

Surgeon2

1 Royal Bolton Hospital, Minerva Road, Bolton BL4 0JR, UK.

2 Stepping Hill Hospital, Poplar Grove, Stockport SK2 7JE, UK.

Correspondence should be sent to Mr A. R. Chitre; e-mail: amolchitre@doctors.org.uk

Intra-articular injections of steroid into the hip are used for a variety of reasons in current orthopaedic practice. Recently their safety prior to ipsilateral total hip replacement has been called into question owing to concerns about deep joint infection.

We undertook a retrospective analysis of all patients who had undergone local anaesthetic and steroid injections followed by ipsilateral total hip replacement over a five-year period. Members of the surgical team, using a lateral approach to the hip, performed all the injections in the operating theatre using a strict aseptic technique.

The mean time between injection and total hip replacement was 18 months (4 to 50).

The mean follow-up after hip replacement was 25.8 months (9 to 78), during which time no case of deep joint sepsis was found.

In our series, ipsilateral local anaesthetic and steroid injections have not conferred an increased risk of infection in total hip replacement. We believe that the practice of intra-articular local anaesthetic and steroid injections to the hip followed by total hip

replacement is safer than previously reported.

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Blood and urine metal ion levels in young and active patients after Birmingham hip resurfacing arthroplasty

FOUR-YEAR RESULTS OF A PROSPECTIVE LONGITUDINAL STUDY

J. Daniel, FRCS, Director of Research1; H. Ziaee, BSc(Hons), Biomedical Scientist1;

C. Pradhan, FRCS, Staff Orthopaedic Surgeon1; P. B. Pynsent, PhD, Director2; and D.

J. W. McMinn, FRCS, Consultant Orthopaedic Surgeon1

1 The McMinn Centre, 25 Highfield Road, Edgbaston, Birmingham B15 3DP, UK.

2 Research and Teaching Centre, Royal Orthopaedic Hospital, Northfield,

Birmingham B31 2AP, UK.

Correspondence should be sent to Mr J. Daniel; e-mail: josephdaniel@mcminncentre.co.uk

This is a longitudinal study of the daily urinary output and the concentrations in whole blood of cobalt and chromium in patients with metal-on-metal resurfacings over a period of four years.

Twelve-hour urine collections and whole blood specimens were collected before and periodically after a Birmingham hip resurfacing in 26 patients. All ion analyses were carried out using a high-resolution inductively-coupled plasma mass spectrometer.

Clinical and radiological assessment, hip function scoring and activity level assessment revealed excellent hip function.

There was a significant early increase in urinary metal output, reaching a peak at six months for cobalt and one year for chromium post-operatively. There was thereafter a

steady decrease in the median urinary output of cobalt over the following three years, although the differences are not statistically significant. The mean whole blood levels of cobalt and chromium also showed a significant increase between the pre-operative and one-year post-operative periods. The blood levels then decreased to a lower level at four years, compared with the one-year levels. This late reduction was statistically significant for chromium but not for cobalt.

The effects of systemic metal ion exposure in patients with metal-on-metal resurfacing arthroplasties continue to be a matter of concern. The levels in this study provide a baseline against which the in vivo wear performance of newer bearings can be compared.

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Changes in the bone mineral density in the acetabulum and proximal femur after cementless total hip replacement

ALUMINA-ON-ALUMINA VERSUS ALUMINA-ON-POLYETHYLENE ARTICULATION

Y.-H. Kim, MD, Professor and Director1; S.-H. Yoon, MD, Clinical Fellow1; and J.-S.

Kim, MD, Associate Professor1

1 The Joint Replacement Center of Korea, Ewha Womans University College of

Medicine, DongDaeMun Hospital, 70, ChongRo 6-Ga, ChongRo-Gu, Seoul 110-783,

Korea.

Correspondence should be sent to Professor Y.-H. Kim; e-mail: younghookim@ewha.ac.kr

Our aim in this prospective study was to compare the bone mineral density (BMD) around cementless acetabular and femoral components which were identical in geometry and had the same alumina modular femoral head, but differed in regard to

the material of the acetabular liners (alumina ceramic or polyethylene) in 50 patients

(100 hips) who had undergone bilateral simultaneous primary total hip replacement.

Dual energy X-ray absorptiometry scans of the pelvis and proximal femur were obtained at one week, at one year, and annually thereafter during the five-year period of the study.

At the final follow-up, the mean BMD had increased significantly in each group in acetabular zone I of DeLee and Charnley (20% (15% to 26%), p = 0.003), but had decreased in acetabular zone II (24% (18% to 36%) in the alumina group and 25%

(17% to 31%) in the polyethylene group, p = 0.001). There was an increase in the mean BMD in zone III of 2% (0.8% to 3.2%) in the alumina group and 1% (0.6% to

2.2%) in the polyethylene group (p = 0.315). There was a decrease in the mean BMD in the calcar region (femoral zone 7) of 15% (8% to 24%) in the alumina group and

14% (6% to 23%) in the polyethylene group (p < 0.001). The mean bone loss in femoral zone 1 of Gruen et al was 2% (1.1% to 3.1%) in the alumina group and 3%

(1.3% to 4.3%) in the polyethylene group (p = 0.03), and in femoral zone 6, the mean bone loss was 15% (9% to 27%) in the alumina group and 14% (11% to 29%) in the polyethylene group compared with baseline values. There was an increase in the mean BMD on the final scans in femoral zones 2 (p = 0.04), 3 (p = 0.04), 4 (p = 0.12) and 5 (p = 0.049) in both groups.

There was thus no significant difference in the bone remodelling of the acetabulum and femur five years after total hip replacement in those two groups where the only difference was in the acetabular liner.

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A modified tibial tubercle osteotomy for patellar maltracking

RESULTS AT TWO YEARS

S. Koëter, MD, Orthopaedic Resident1; M. J. F. Diks, MD, Orthopaedic Surgeon2; P. G.

Anderson, MA, Orthopaedic Researcher3; and A. B. Wymenga, MD, PhD,

Orthopaedic Surgeon3

1 Department of Orthopaedic Surgery, Rijnstate Hospital, PO Box 9555, 6800 TA,

Arnhem, The Netherlands.

2 Department of Orthopaedic Surgery, Ysselland Hospital, Prins Constantijnweg 2,

2906 ZC Capelle aan de Yssel, The Netherlands.

3 Department of Orthopaedic Surgery, St Maartenskliniek, PO Box 9011, 6500 GM

Nijmegen, The Netherlands.

Correspondence should be sent to Dr A. B. Wymenga; e-mail: a.wymenga@maartenskliniek.nl

An abnormal lateral position of the tibial tuberosity causes distal malalignment of the extensor mechanism of the knee and can lead to lateral tracking of the patella causing anterior knee pain or objective patellar instability, characterised by recurrent dislocation. Computer tomography is used for a precise pre-operative assessment of the tibial tubercle-trochlear groove distance. A distance of more than 15 mm is considered to be pathological and an indication for surgery in symptomatic patients.

In a prospective study we performed a subtle transfer of the tibial tuberosity according to the information gained from the pre-operative CT scan. This method was applied to two groups of patients, those with painful lateral tracking of the patella, and those with objective patellar instability. We evaluated the clinical results in 30 patients in each group. The outcome was documented at 3, 12 and 24 months using the Lysholm scale, the Kujala score, and a visual analogue pain score.

Post-operatively, all but one patient in the instability group who had a patellar dislocation requiring further surgery reported good improvement with no further

subluxation or dislocation. All patients in both groups had a marked improvement in pain and functional score. Two patients sustained a tibial fracture six and seven weeks after surgery. One patient suffered a per-operative fracture of the tibial tubercle which later required further fixation.

If carefully performed, this type of transfer of the tibial tubercle appears to be a satisfactory technique for the treatment of patients with an increased tibial tubercle-trochlear groove distance and who present with symptoms related to lateral maltracking of the patella.

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Total knee replacement in haemophilic arthropathy

E. C. Rodriguez-Merchan, MD, PhD, Orthopaedic Surgeon, Associate Professor1

1 Department of Orthopaedics and Haemophilia Unit, La Paz University Hospital,

Paseo de la Castellana 261, 28046 Madrid, Spain.

Correspondence should be sent to Dr E. C. Rodriguez-Merchan at Capitan Blanco

Argibay 21-G-3A, 28029 Madrid, Spain; e-mail: rmerchan@arrakis.es

The results of primary total knee replacement performed on a group of haemophiliac patients in a single institution by the same surgeon using the same surgical technique and prosthesis are reported.

A total of 35 primary replacements in 30 patients were carried out between 1996 and

2005 and were reviewed retrospectively. The mean age of the patients was 31 years

(24 to 42) and the mean follow-up was for 7.5 years (1 to 10). There were 25 patients with haemophilia A and five with haemophilia B. The HIV status and CD4 count were

recorded, and Knee Society scores determined. Two patients had inhibitors to the deficient coagulation factor.

There were no early wound infections and only one late deep infection which required a two-stage revision arthroplasty, with a good final result. The incidence of infection in

HIV-positive and negative patients was thus similar. One knee in a patient with inhibitor had excessive bleeding due to a pseudoaneurysm which required embolisation. The results were excellent in 27 knees (77%), good in six (17%) and fair in two (6%). The survival rate at 7.5 years taking removal of the prosthesis for loosening or infection as the end-point was 97%.

The mechanical survival of total knee replacements in haemophiliacs is very good.

Our results confirm that this is a reproducible procedure in haemophilia, even in

HIV-positive patients with a CD4 count > 200 mm3 and those with inhibitors. Our rate of infection was lower than previously reported. This could be due to better control of the HIV status with highly active anti-retroviral therapy and the use of antibiotic-loaded cement.

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Use of the reverse shoulder prosthesis for the treatment of failed hemiarthroplasty in patients with glenohumeral arthritis and rotator cuff deficiency

J. C. Levy, MD, Orthopaedic Surgeon1; N. Virani, MD, Research Fellow2; D. Pupello,

BS, MBA, Consultant Researcher, Research Manager2; and M. Frankle, MD,

Orthopaedic Surgeon2

1 Orthopaedic Institute at Holy Cross, Fort Lauderdale, 33308 Florida, USA.

2 Florida Orthopaedic Institute, 13020 Telecom Parkway North, Temple Terrace,

Florida 33637, USA.

Correspondence should be sent to Dr M. Frankle; e-mail: dpupello@floridaortho.com

We report the use of the reverse shoulder prosthesis in the revision of a failed shoulder hemiarthroplasty in 19 shoulders in 18 patients (7 men, 11 women) with severe pain and loss of function. The primary procedure had been undertaken for glenohumeral arthritis associated with severe rotator cuff deficiency.

Statistically significant improvements were seen in pain and functional outcome. After a mean follow-up of 44 months (2 4 to 89), mean forward flexion improved by 26.4° and mean abduction improved by 35°. There were six prosthesis-related complications in six shoulders (32%), five of which had severe bone loss of the glenoid, proximal humerus or both. Three shoulders (16%) had non-prosthesis related complications.

The use of the reverse shoulder prosthesis provides improvement in pain and function for patients with failure of a hemiarthroplasty for glenohumeral arthritis and rotator cuff deficiency. However, high rates of complications were associated with glenoid and proximal humeral bone loss.

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Proximal scaphoid rib graft arthroplasty

S. Veitch, MD, MRCS, Orthopaedic Specialist Registrar1; S. M. Blake, BSc, MBBS,

MRCS, Orthopaedic Specialist Registrar2; and H. David, FRCS, FRCS(Orth),

Consultant Orthopaedic Surgeon3

1 Princess Elizabeth Orthopaedic Centre, Royal Devon and Exeter Hospital, Barrack

Road, Exeter, EX2 5DW, UK.

2 Department of Orthopaedic Surgery, Torbay Hospital, Newton Road, Torquay,

Devon TQ2 7AA, UK.

3 Derriford Hospital, Derriford Road, Crownhill, Plymouth, PL6 8DH, UK.

Correspondence should be sent to Dr S. Veitch; e-mail: swveitch@doctors.org.uk

We prospectively reviewed 14 patients with deficiency of the proximal pole of the scaphoid who were treated by rib osteochondral replacement arthroplasty.

Improvement in wrist function occurred in all except one patient with enhanced grip strength, less pain and maintenance of wrist movement. In 13 patients wrist function was rated as good or excellent according to the modified wrist function score of Green and O’Brien. The mean pre-operative score of 54 (35 to 80) rose to 79 (50 to 90) at review at a mean of 64 months (27 to 103). Carpal alignment did not deteriorate in any patient and there were no cases of nonunion or significant complications.

This procedure can restore the mechanical integrity of the proximal pole of the scaphoid satisfactorily and maintain wrist movement while avoiding the potential complications of alternative replacement arthroplasty techniques and problems associated with vascularised grafts and salvage techniques.

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Visualisation of the pisotriquetral joint through standard portals for arthroscopy of the wrist

A CLINICAL AND ANATOMICAL STUDY

A. P. Arya, MS(Orth), MChOrth, Associate Specialist1; R. Kulshreshtha, MRCS, Junior

Clinical Fellow1; G. K. Kakarala, MRCSEd, Orthopaedic Registrar2; R. Singh,

FRCS(Tr & Orth), Consultant Orthopaedic Surgeon3; and J. P. Compson,

FRCS(Tr&Orth), Consultant Orthopaedic Surgeon1

1 Upper Limb Unit, Department of Trauma & Orthopaedic Surgery, Kings College

Hospital, Denmark Hill, London SE5 9RS, UK.

2 New Cross Hospital, Wednesfield Road, Wolverhampton WV10 0Q8, UK.

3 Wrexham Maelor Hospital, Croesnewydd Road, Wrexham, LL13 7TD, UK.

Correspondence should be sent to Mr A. P Arya; e-mail: anandparya@gmail.com

Disorders of the pisotriquetral joint are well recognised as the cause of pain on the ulnar side of the wrist. The joint is not usually examined during routine arthroscopy because it is assumed to have a separate joint cavity to the radiocarpal joint, although there is often a connection between the two.

We explored this connection during arthroscopy and in fresh-frozen cadaver wrists and found that in about half of the cases the pisotriquetral joint could be visualised through standard wrist portals. Four different types of connection were observed between the radiocarpal joint and the pisotriquetral joint. They ranged from a complete membrane separating the two, to no membrane at all, with various other types of connection in between.

We recommend that inspection of the pisotriquetral joint should be a part of the protocol for routine arthroscopy of the wrist.

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Gradual joint distraction of post-traumatic flexion contracture of the proximal interphalangeal joint by a mini-external fixator

S. Houshian, MD, Consultant Orthopaedic Surgeon1; C. Chikkamuniyappa, MS(Orth),

DNB(Orth), Registrar in Orthopaedics1; and H. Schroeder, MD, Consultant Hand

Surgeon2

1 Department of Orthopaedics, University Hospital Lewisham, High Street, Lewisham,

London, SE13 6LH, UK.

2 Department of Orthopaedics, Odense University Hospital, Sdr. Boulevard 29, 5000,

Odense, Denmark.

Correspondence should be sent to Mr S. Houshian; e-mail: shirzad.houshian@uhl.nhs.uk

We present the outcome of the treatment of chronic post-traumatic contractures of the proximal interphalangeal joint by gradual distraction correction using an external fixator. A total of 30 consecutive patients with a mean age of 34 years (17 to 54) had distraction for a mean of 16 days (10 to 22). The fixator was removed after a mean of

29 days (16 to 40). Assessment at a mean of 34 months (18 to 54) after completion of treatment showed that the mean active range of movement had significantly increased by 63° (30° to 90°; p < 0.001). The mean active extension gained was 47°

(30° to 75°).

Patients aged less than 40 years fared slightly better with a mean gain in active range of movement of 65° (30° to 90°) compared with those aged more than 40 years, who had a mean gain in active range of movement of 55° (30° to 70°) but the difference was not statistically significant (p = 0.148).

The use of joint distraction to correct chronic flexion contracture of the proximal interphalangeal joint is a minimally-invasive and effective method of treatment.

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Posterior lumbar interbody fusion and posterior instrumentation in the surgical management of lumbar tuberculous spondylitis

J. S. Lee, MD, Orthopaedic Surgeon, Assistant Professor1; K. P. Moon, MS,

Orthopaedic Surgeon1; S. J. Kim, MD, Nuclear Physician, Assistant Professor2; and

K. T. Suh, MD, Orthopaedic Surgeon, Professor1

1 Department of Orthopaedic Surgery

2 Department of Nuclear Medicine, Pusan National University, School of Medicine,

1-10 Ami-Dong, Seo-Gu, Pusan 602-739, Korea.

Correspondence should be sent to Professor K. T. Suh; e-mail: kuentak@pusan.ac.kr

There are few reports of the treatment of lumbar tuberculous spondylitis using the posterior approach. Between January 1999 and February 2004, 16 patients underwent posterior lumbar interbody fusion with autogenous iliac-bone grafting and pedicle screw instrumentation. Their mean age at surgery was 51 years (28 to 66).

The mean follow-up period was 33 months (24 to 48). The clinical outcome was assessed using the Frankel neurological classification and the Kirkaldy-Willis criteria.

On the Frankel classification, one patient improved by two grades (C to E), seven by one grade, and eight showed no change. The Kirkaldy-Willis functional outcome was classified as excellent in eight patients, good in five, fair in two and poor in one. Bony union was achieved within one year in 15 patients. The mean pre-operative lordotic angle was 27.8° (9° to 45°) which improved by the final follow-up to 35.8° (28° to 48°).

Post-operative complications occurred in four patients, transient root injury in two, a superficial wound infection in one and a deep wound infection in one, in whom the implant was removed.

Our results show that a posterior lumbar interbody fusion with autogenous iliac-bone

grafting and pedicle screw instrumentation for tuberculous spondylitis through the posterior approach can give satisfactory results.

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Reconstruction with non-vascularised fibular grafts after resection of bone tumours

A. H. Krieg, MD, Orthopaedic Surgeon1; and F. Hefti, MD, Orthopaedic Surgeon,

Professor1

1 Orthopaedic Department Children’s Hospital, University of Basel (UKBB), P O Box

4005, Basel, Switzerland.

Correspondence should be sent to Dr A. H. Krieg; e-mail: andreas.krieg@ukbb.ch

We evaluated 31 patients who were treated with a non-vascularised fibular graft after resection of primary musculoskeletal tumours, with a median follow-up of 5.6 years (3 to 26.7 years). Primary union was achieved in 89% (41 of 46) of the grafts in a median period of 24 weeks. All 25 grafts in 18 patients without additional chemotheraphy and/or radiotherapy achieved primary union, compared with 16 of the 21 grafts (76%;

13 patients) with additional therapy (p = 0.017). Radiographs showed an increase in diameter in 70% (59) of the grafts. There were seven fatigue fractures in six patients, but only two needed treatment.

Non-vascularised fibular transfer is a simpler, less expensive and a shorter procedure than the use of vascularised grafts and allows remodelling of the fibula at the donor site. It is a biological reconstruction with good long-term results, and a relatively low donor site complication rate of 16%.

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Unicameral bone cysts

A COMPARISON OF INJECTION OF STEROID AND GRAFTING WITH

AUTOLOGOUS BONE MARROW

H. S. Cho, MD, Orthopaedic Surgeon1; J. H. Oh, MD, PhD, Professor2; H.-S. Kim,

MD, PhD, Professor3; H. G. Kang, MD, Orthopaedic Surgeon1; and S. H. Lee, MD,

PhD, Professor3

1 Orthopaedic Oncology Clinic, National Cancer Center, 809, Madu 1-dong,

Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769, Korea.

2 Department of Orthopaedic Surgery, Seoul National University, Bundang Hospital,

300 Goomi-dong, Bundang-gu, Seongnam-si, Gyeonggi-do 463-707, Korea.

3 Department of Orthopaedic Surgery, Seoul National University Hospital, 28

Yongon-dong, Chongno-gu, Seoul 110-744, Korea.

Correspondence should be sent to Professor J. H. Oh; e-mail: ohjh1@snu.ac.kr

Open surgery is rarely justified for the initial treatment of a unicameral bone cyst, but there is some debate concerning the relative effectiveness of closed methods. This study compared the results of steroid injection with those of autologous bone marrow grafting for the treatment of unicameral bone cysts. Between 1990 and 2001, 30 patients were treated by steroid injection and 28 by grafting with autologous bone marrow. The overall success rates were 86.7% and 92.0%, respectively (p > 0.05).

The success rate after the initial procedure was 23.3% in the steroid group and 52.0% in those receiving autologous bone marrow (p < 0.05), and the respective cumulative success rates after second injections were 63.3% and 80.0% (p > 0.05). The mean number of procedures required was 2.19 (1 to 5) and 1.57 (1 to 3) (p < 0.05), the mean interval to healing was 12.5 months (4 to 32) and 14.3 months (7 to 36) (p >

0.05), and the rate of recurrence after the initial procedure was 41.7% and 13.3% in

the steroid and in the autologous bone marrow groups, respectively (p < 0.05).

Although the overall rates of success of both methods were similar, the steroid group had higher recurrence after a single procedure and required more injections to achieve healing.

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Metacarpophalangeal joint dislocation of the thumb in children

R. Maheshwari, MBBS, MRCS(Edin), MSc(Orth Eng), Orthopaedic Surgeon1; H.

Sharma, MBBS, FRCS, Specialist Registrar in Orthopaedics2; and R. D. D. Duncan,

FRCS(Orth), Consultant in Paediatric Orthopaedics2

1 Doncaster Royal Infirmary, Doncaster DN2 5LT, South Yorkshire, UK.

2 Royal Hospital for Sick Children, Yorkhill, Glasgow G3 8SJ, UK.

Correspondence should be sent to Mr R. Maheshwari; e-mail: rajanmh@aol.com

There are few reports describing dislocation of the metacarpophalangeal joint of the thumb in children. This study describes the clinical features and outcome of 37 such dislocations and correlates the radiological pattern with the type of dislocation.

The mean age at injury was 7.3 years (3 to 13). A total of 33 children underwent closed reduction (11 under general anaesthesia). Four needed open reduction in two of which there was soft-tissue interposition. All cases obtained a good result. There was no infection, recurrent dislocation or significant stiffness.

Socalled ‘simple complete’ dislocations that present with the classic radiological finding of the joint at 90° dorsal angulation may be ‘complex complete’ injuries and

require open reduction.

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Treatment for developmental dysplasia of the hip using the Pavlik harness

LONG-TERM RESULTS

J. Nakamura, MD, Resident1; M. Kamegaya, MD, Chief Staff Surgeon2; T. Saisu, MD,

Staff Surgeon2; M. Someya, MD, Chief Staff Surgeon3; W. Koizumi, MD, Staff

Surgeon4; and H. Moriya, MD, Professor1

1 Department of Orthopaedic Surgery Graduate School of Medicine, Chiba University,

1-8-1 Inohana, Chuo-ku, Chiba City, 260-8677, Japan.

2 Division of Orthopaedic Surgery Chiba Children’s Hospital, 579-1 Heta-chou,

Midori-ku, Chiba City, 266-0007, Chiba, Japan.

3 Division of Pediatric Orthopaedic Surgery Chiba Rehabilitation Center, 1-45-2

Honda-chou, Midori-ku, Chiba City, 266-0005, Chiba, Japan.

4 Division of Orthopaedic Surgery Narita Red Cross Hospital, 90-1 Iida-chou, Narita

City, 286-8523, Chiba, Japan.

Correspondence should be sent to Dr J. Nakamura; e-mail: njonedr@yahoo.co.jp

We reviewed the medical records of 115 patients with 130 hips with developmental dysplasia with complete dislocation in the absence of a neuromuscular disorder, spontaneous reduction with a Pavlik harness, and a minimum of 14 yea rs’ follow-up.

The mean age at the time of harness application was 4.8 months (1 to 12) and the mean time spent in the harness was 6.1 months (3 to 12). A total of 108 hips (83.1%) were treated with the harness alone and supplementary surgery for residual acetabular dysplasia, as defined by an acetabular index > 30°, was performed in 22 hips (16.9%).

An overall satisfactory outcome (Severin grade I or II) was achieved in 119 hips

(91.5%) at a mean follow-up of 16 years (14 to 32) with a follow-up rate of 75%.

Avascular necrosis of the femoral head was noted in 16 hips (12.3%), seven of which

(44%) underwent supplementary surgery and nine (56%) of which were classified as satisfactory. The acetabular index was the most reliable predictor of residual acetabular dysplasia.

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Outcome after corrective osteotomy for malunited fractures of the forearm sustained in childhood

R. C. I. van Geenen, MD, PhD, Orthopaedic Specialist Registrar1; and P. P. Besselaar,

MD, PhD, Orthopaedic Surgeon2

1 Keizersgracht 535, 1017 DP, Amsterdam, The Netherlands.

2 Department of Orthopaedic Surgery, Academic Medical Centre, G4-N, P. O. Box

22660, 1100 DD, Amsterdam, The Netherlands.

Correspondence should be sent to Dr R. C. I. van Geenen; e-mail: rcivangeenen@hotmail.com

We analysed the operative technique, morbidity and functional outcome of osteotomy and plate fixation for malunited fractures of the forearm sustained in childhood.

A total of 20 consecutive patients underwent corrective osteotomy of 21 malunited fractures at a mean age of 12 years (4 to 25). The mean time between the injury and the osteotomy was 30 months (2 to 140).

After removal of the plate, one patient suffered transient dysaesthesia of the

superficial radial nerve. The mean gain in the range of movement was 85° (20° to

140°). The interval between injury and osteotomy, and the age at osteotomy significantly influenced the functional outcome (p = 0.011 and p = 0.004, respectively).

Malunited fractures of the forearm sustained in childhood can be adequately treated by osteotomy and plate fixation with excellent functional results and minimal complications. In the case of established malunion it is advisable to perform corrective osteotomy without delay.

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Near-fatal air embolus during arthrography of the hip in a baby aged four months

R. Lamdan, MD, Orthopaedic Surgeon1; A. Sadun, MD, Orthopaedic Surgeon1; and

M. Y. Shamir, MD, Anaesthesiologist1

1 Department of Orthopaedics, Hassadah University Hospital, Hebrew University

School of Medicine, PO Box 12000, Jerusalem 91120, Israel.

Correspondence should be sent to Dr R. Lamdan; e-mail: nrlamdan@bezeqint.net

We describe a near-fatal event, probably due to air embolism, following an air arthrogram for developmental hip dysplasia in a baby aged four months. The sequence of events and the subsequent treatment are described. There is little information about this complication in the literature. The presumed mechanism and alternative methods for confirmation of placement of the needle are discussed. We no longer use air arthrography in children.

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Sciatic nerve injury caused by pre-operative intraneural injection of local anaesthetic during total hip replacement

H. S. Uppal, MRCS, Senior House Officer in Orthopaedics1; S. E. Gwilym, MRCS,

Specialist Registrar in Orthopaedics1; E. J. P. Crawfurd, FRCS, Consultant

Orthopaedic Surgeon1; and R. Birch, MChir, FRCS, Orthopaedic Surgeon2

1 Northampton General Hospital, Cliftonville, Northampton NN1 5BD, UK.

2 Peripheral Nerve Injury Unit, Royal National Orthopaedic Hospital, Brockley Hill,

Stanmore, Middlesex HA7 4LP, UK.

Correspondence should be sent to Mr E. J. P. Crawfurd; e-mail: edward.crawfurd@ngh.nhs.uk

We report a case of iatrogenic sciatic nerve injury caused by pre-operative intraneural injection of local anaesthetic at total hip replacement. To our knowledge, this is unreported in the orthopaedic literature. We consider sacral nerve blockade in patients undergoing total hip replacement to be undesirable and present guidelines for the management of peri-operative sciatic nerve injury.

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Hair tourniquet syndrome in an infant

R. A. Haene, MBBCh MRCSEd, Orthopaedic Specialist Registrar1; and M. Loeffler,

FRCS(Eng), FRCS(Orth), MBBS, Orthopaedic Consultant1

1 Department of Orthopaedic Surgery Colchester General Hospital, Turner Road,

Colchester, Essex CO4 5JL, UK.

Correspondence should be sent to Mr R. A. Haene; e-mail: roger@haene.org

An 11-week-old infant presented with swelling and discoloration of the left second toe because of hair thread tourniquet syndrome. This was treated by urgent surgical release of the constricting band, with a successful outcome. The authors stress the importance of recognising this rare condition and of prompt, complete, surgical release.

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Restoration of shoulder function and elbow flexion by nerve transfer for poliomyelitis-like paralysis caused by enterovirus 71 infection

S. Funahashi, MD, Orthopaedic Surgeon1; A. Nagano, MD, PhD, Orthopaedic

Surgeon, Professor1; M. Sano, MD, PhD, Orthopaedic Surgeon1; H. Ogihara, MD,

Orthopaedic Surgeon1; and T. Omura, MD, PhD, Orthopaedic Surgeon1

1 Department of Orthopaedic Surgery, Hamamatsu University School of Medicine,

1-20-1 Handayama, Hamamatsu, Shizuoka 431-3192, Japan.

Correspondence should be sent to Dr S. Funahashi; e-mail: funal5@hama-med.ac.jp

We report the case of an eight-month-old girl who presented with a poliomyelitis-like paralysis in her left upper limb caused by enterovirus 71 infection. She recovered useful function after nerve transfers performed six months after the onset of paralysis.

Early neurotisation can be used successfully in the treatment of poliomyelitis-like paralysis in children.

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Multifocal Proteus mirabilis osteomyelitis requiring bilateral amputation in an

HIV-positive patient

G. Petsatodis, MD, PhD, Associate Professor of Orthopaedics1; P. D. Symeonidis, MD,

Orthopaedic Surgeon1; D. Karataglis, MD, PhD, Orthopaedic Surgeon1; and J.

Pournaras, MD, PhD, Professor of Orthopaedics1

1 1st Orthopaedic Department Aristotle University of Thessalonika, "G. Papanikolaou"

Hospital, 57010 Exohi, Thessaloniki, Greece.

Correspondence should be sent to Dr P. D. Symeonidis; e-mail: p.symeonidis@gmail.com

We present a rare case of multifocal Proteus mirabilis osteomyelitis in an HIV-positive patient. Despite the patient’s good immune status as assessed by her CD4 cell count and the aggressive treatment, she eventually underwent bilateral above-knee amputations to eradicate the infection. Multifocal Proteus mirabilis osteomyelitis can have an unpredictable clinical course with a severe outcome in HIV-positive patients.

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A biomechanical comparison of kyphoplasty using a balloon bone tamp versus an expandable polymer bone tamp in a deer spine model

E. H. Seel, BM, MRCS, CertMedEd, Specialist Registrar in Orthopaedics1; and E. M.

Davies, BM, FRCS(Tr & Orth), Consultant Spinal Surgeon1

1 Department of Orthopaedics, Southampton University, Hospitals NHS Trust,

Southampton General Hospital, Tremona Road, Southampton SO16 6YD, UK.

Correspondence should be sent to Mr E. H. Seel; e-mail:

edward@eseel.wanadoo.co.uk

We performed a biomechanical study to compare the augmentation of isolated fractured vertebral bodies using two different bone tamps. Compression fractures were created in 21 vertebral bodies harvested from red deer after determining their initial strength and stiffness, which was then assessed after standardised bipedicular vertebral augmentation using a balloon or an expandable polymer bone tamp.

The median strength and stiffness of the balloon bone tamp group was 6.71 kN (SD

2.71) and 1.885 kN/mm (SD 0.340), respectively, versus 7.36 kN (SD 3.43) and 1.882 kN/mm (SD 0.868) in the polymer bone tamp group. The strength and stiffness tended to be greater in the polymer bone tamp group than in the balloon bone tamp group, but this difference was not statistically significant (strength p > 0.8, and stiffness p =

0.4).

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Repair of osteochondral defects with a new porous synthetic polymer scaffold

I. Nagura, MD, Orthopaedic Surgeon1; H. Fujioka, MD, Lecturer1; T. Kokubu, MD,

Orthopaedic Surgeon1; T. Makino, MD, Research Associate1; Y. Sumi, PhD, Group

Leader, Senior Manager2; and M. Kurosaka, MD, Professor and Chairman1

1 Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine,

7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan.

2 Department of Tissue, Engineering Development, Innovation Research Institute,

TEIJIN Limited, 4-3-2 Asahigaoka, Hino, Tokyo 191-8512, Japan.

Correspondence should be sent to Dr H. Fujioka; e-mail: hfujioka@med.kobe-u.ac.jp

We developed a new porous scaffold made from a synthetic polymer, poly(DL-lactide-co-glycolide) (PLG), and evaluated its use in the repair of cartilage.

Osteochondral defects made on the femoral trochlear of rabbits were treated by transplantation of the PLG scaffold, examined histologically and compared with an untreated control group.

Fibrous tissue was initially organised in an arcade array with poor cellularity at the articular surface of the scaffold. The tissue regenerated to cartilage at the articular surface. In the subchondral area, new bone formed and the scaffold was absorbed.

The histological scores were significantly higher in the defects treated by the scaffold than in the control group (p < 0.05).

Our findings suggest that in an animal model the new porous PLG scaffold is effective for repairing full-thickness osteochondral defects without cultured cells and growth factors.

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RhBMP-7 accelerates the healing in distal tibial fractures treated by external fixation

J. Ristiniemi, MD, Orthopaedic and Trauma Surgeon1; T. Flinkkilä, MD, PhD,

Orthopaedic and Trauma Surgeon1; P. Hyvönen, MD, PhD, Orthopaedic and Trauma

Surgeon1; M. Lakovaara, MD, Orthopaedic and Trauma Surgeon1; H. Pakarinen, MD,

Orthopaedic and Trauma Surgeon1; and P. Jalovaara, MD, PhD, Professor of

Orthopaedic and Trauma Surgery1

1 Department of Orthopaedic and Trauma Surgery, University Hospital of Oulu, P.O.

Box 90029, OYS, Oulu, Finland.

Correspondence should be sent to Dr J. Ristiniemi; e-mail: Jukka.Ristiniemi@oulu.fi

External fixation of distal tibial fractures is often associated with delayed union. We have investigated whether union can be enhanced by using recombinant bone morphogenetic protein-7 (rhBMP-7).

Osteoinduction with rhBMP-7 and bovine collagen was used in 20 patients with distal tibial fractures which had been treated by external fixation (BMP group). Healing of the fracture was compared with that of 20 matched patients in whom treatment was similar except that rhBMP-7 was not used.

Significantly more fractures had healed by 16 (p = 0.039) and 20 weeks (p = 0.022) in the BMP group compared with the matched group. The mean time to union (p =

0.002), the duration of absence from work (p = 0.018) and the time for which external fixation was required (p = 0.037) were significantly shorter in the BMP group than in the matched group. Secondary intervention due to delayed healing was required in two patients in the BMP group and seven in the matched group.

RhBMP-7 can enhance the union of distal tibial fractures treated by external fixation.

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Wear analysis of failed acetabular polyethylene

A COMPARISON OF ANALYTICAL METHODS

G. S. J. Chuter, MRCS, Orthopaedic Specialist Registrar1; D. J. Cloke, MRCS,

Orthopaedic Specialist Registrar2; A. Mahomed, MEng, PhD Student3; P. F.

Partington, FRCS(Orth), Consultant Orthopaedic Surgeon2; and S. M. Green, PhD,

Senior Lecturer3

1 Sunderland Royal Hospital, Kayll Road, Sunderland SR4 7TA, UK.

2 Orthopaedic Department, Wansbeck General Hospital, Woodhorn Lane, Ashington,

Northumberland NE63 9JJ, UK.

3 School of Engineering, University of Durham, Durham DH1 3LE, UK.

Correspondence should be sent to Mr G. S. J. Chuter; e-mail: gchuter@hotmail.com

There are many methods for analysing wear volume in failed polyethylene acetabular components. We compared a radiological technique with three recognised ex vivo methods of measurement.

We tested 18 ultra-high-molecular-weight polyethylene acetabular components revised for wear and aseptic loosening, of which 13 had pre-revision radiographs, from which the wear volume was calculated based upon the linear wear. We used a shadowgraph technique on silicone casts of all of the retrievals and a coordinate measuring method on the components directly. For these techniques, the wear vector was calculated for each component and the wear volume extrapolated using mathematical equations. The volumetric wear was also measured directly using a fluid-displacement method. The results of each technique were compared.

The series had high wear volumes (mean 1385 mm3; 730 to 1850) and high wear rates (mean 205 mm3/year; 92 to 363). There were wide variations in the measurements of wear volume between the radiological and the other techniques.

Radiograph-derived wear volume correlated poorly with that of the fluid-displacement method, co-ordinate measuring method and shadowgraph methods, becoming less accurate as the wear increased. The mean overestimation in radiological wear volume was 47.7% of the fluid-displacement method wear volume.

Fluid-displacement method, coordinate measuring method and shadowgraph determinations of wear volume were all better than that of the radiograph-derived linear measurements since they took into account the direction of wear. However, only

radiological techniques can be used in vivo and remain useful for monitoring linear wear in the clinical setting.

Interpretation of radiological measurements of acetabular wear must be done judiciously in the clinical setting. In vitro laboratory techniques, in particular the fluid-displacement method, remain the most accurate and reliable methods of assessing the wear of acetabular polyethylene.

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