Restoration of anatomy is paramount in total hip arthroplasty (THA) to optimise function and stability. Leg-length discrepancy of ≥10mm is poorly tolerated and can be the subject of litigation. We routinely use a multimodal protocol to optimise soft tissue balancing which involves pre-operative templating, leg-length measurement supine and in the lateral position after positioning, and the use of an intra-operative leg-length measurement device to ensure optimisation of leg-length. We have analysed the results of our protocol in restoring leg-length in primary THA. Radiological leg-length was measured in a consecutive series of 50 patients who had THA for unilateral arthritis by an independent observer pre- and post-operatively using validated methods utilising radiological software. The measurements pre- and post-operative were compared. Patients with bilateral hip arthritis and poor imaging were excluded. Leg-length was successfully restored to within 5.0mm of the target leg-length in 84.0% of patients (mean +0.7mm (95% CI +0.2 to +1.1)). The other 14.0% of patients were restored to within 5.1–8.0mm (mean +2.2mm (95% CI −2.7 to +7.1)) and 2.0% of patients were restored to within 8.1–10.0mm. Leg length was accurately restored across the subset of patients within a narrow range of either side of the mean target leg length. Intra-operative measurement of leg length can be difficult but is vital in ensuring appropriate restoration of leg-length. We recommend a similar multimodal protocol to ensure restoration of leg-length within narrow limits to maximise function and patient satisfaction.

Introduction

Restoration of anatomy is essential in total hip arthroplasty (THA) to optimize function and stability. Leg-length discrepancy of ≥10mm is poorly tolerated and can be the subject of litigation. We use a multimodal protocol to optimize soft tissue balancing which involves pre- operative templating, leg-length measurement supine and after positioning, use of an intra-operative leg-length and offset measurement device and implants with standard and high-offset options.

Introduction

The aim is to study the outcome of a consecutive single surgeon's series using the ReCap Hip resurfacing arthroplasty (HRA) system.

Background

It has been suggested that routine follow-up of primary THR patients could be performed by GPs in primary care, rather than by orthopaedic specialists. Essential radiographic follow-up would likely be based on radiographic reports, rather than on inspection of the radiographs themselves.

Introduction: We describe a novel, innovative and inexpensive method of producing a reinforced articulating cement spacer using a commercially available hip cement mould.

Methods: After adequate debridement and removal of original implants during the first of a two-stage revision procedure, an articulating cement spacer is created using a conventional mould and is reinforcing using a central stainless steel rod extending from the head to the tip using a novel technique that will be described in detail.

Results: We currently have a cohort of six consecutive patients in whom this novel cement spacer has been used. All patients were able to at least partially weight bear and none of the spacers fractured. Five have been explanted at second stage surgery after a minimum of 8 weeks in situ. One patient has been unable to undergo a second stage due to medical co morbidities and continues to mobilise with walking aids on the spacer 1-year post implantation.

Discussion: The articulating cement spacer described is produced using a technique that is simple, reproducible and allows a reinforced spacer to be created inexpensively without the need for special equipment. The spacer described provides a number of advantages over previously described or currently available commercial cement spacers. As it is reinforced it provides increased strength and allows partial weight bearing without risk of spacer fracture, a recognised complication of unreinforced spacers. As it uses a mould the surface remains smooth allowing easier insertion and minimising further bone loss with articulation. As it is fabricated intra-operatively, rather than being premanufactured, antibiotics can be added to the cement used to make the spacer according to known organism sensitivities.

Conclusion: We describe the first ever smooth, articulating, moulded cement spacer that can be inexpensively fabricated intra-operatively without the requirement for special equipment.

Introduction: One of the most common complications following total joint surgery is aseptic loosening. Improving the bone-cement interlock may increase implant longevity. An ideally prepared bony surface is dry; clean; free from marrow, fat and debris; free from active bleeding; and free from micro-organisms. Lavage removes debris, blood and fat from the interstices of the bone surface so as to allow optimal penetration of the cement. The hypothesis that we investigated in this study was that lavage with a detergent solution obtains a greater depth of cement penetration into bone compared with lavage using 0.9% saline, hydrogen peroxide or an alcohol solution.

Methods: The cancellous bone of ovine femoral condyles were cut into 10×10×13mm blocks. Lavage solutions were delivered via a pulsatile system and directed towards one side of the bone block. All blocks were swabbed dry. A high viscosity cement was manually mixed and applied to the sandblasted surface of titanium alloy plate (10×10mm, weight 0.9g ±0.01g). The titanium plate and cement were placed on the irrigated bone block, and a known weight applied to achieve pressurisation. Time, temperature and method were controlled. The prosthesis-cement-bone composite was sectioned perpendicularly, and image analysis used to quantify penetration depths. 10 readings were recorded per block with 6 blocks per lavage group.

Results: Cancellous bone porosity averaged 75.2% (±4.0) . The mean penetration depth in the saline group averaged 3.39mm (± 0.77); 3.04mm (± 0.59) using a 2% alcohol solution; 3.33mm (±0.79) using a 3% hydrogen peroxide solution; and 5.41mm (± 1.30) when using the detergent lavage. There was no significant difference in cement penetration depth between hydrogen peroxide and saline irrigation (p> 0.05), nor with hydrogen peroxide and alcohol irrigation (p> 0.05). Irrigation with saline however, afforded statistically superior cement penetration than that of alcohol lavage (p < 0.012). Irrigation with detergent solution demonstrated significantly greater depth of penetration than all three other lavage groups (saline p< 0.05; alcohol p< 0.05; hydrogen peroxide p< 0.05).

Discussion: Detergents can physically remove particulate matter and emulsify and remove fats, thereby acting to maximise porosity of the cancellous bone network and optimise space for occupation by intruding cement. This study has proven the ability of a detergent solution to provide a clean, debris free cancellous network, which consequently provides a significantly greater depth of cement penetration than other commonly used irrigating agents. It was noted that cement penetration into cancellous bone followed the line and depth of cleaning from lavage. In conclusion, the hypothesis can be accepted, and lavage with a detergent solution affords a statistically greater depth of cement penetration into bone than that of the universally used 0.9% saline lavage.

Introduction: Autologous chondrocyte implantation (ACI) is a technique described for treating symptomatic osteochondral defects in the knee. It is contra-indicated, however, in a joint rendered unstable by a ruptured anterior cruciate ligament (ACL). We present our early experience of combined ACL and ACI repair.

Methods: Patients underwent arthroscopic examination and cartilage harvesting of the knee. Chondrocytes were then cultured in plasma and a second operation was undertaken approximately four weeks later to repair the ruptured ACL with hamstring graft and to implant the chondrocytes via formal arthrotomy. Patients then underwent a graduated rehabilitation program and were reviewed at 6 and 12 months. Functional measurements were made using the Bentley functional scale and the modified Cincinnati rating system, with pain measured on a visual analogue scale. All patients also underwent formal clinical examination at each review.

Results: 4 out of the 5 patients reported an improvement in pain as measured on visual analogue scale, with 1 patient reporting no difference. 4 patients had stable knees as determined by negative anterior draw, negative Lachman’s test and negative pivot shift test; one patient showed improvement, but remained pivot shift positive. Improvements in Bentley scores were noted in 3 patients. Cincinnati scores were markedly improved in 3 patients and slightly improved in the remaining 2 patients. The only operative complications were a traction neuropraxia to the saphenous nerve of one patient requiring no treatment and a manipulation under anaesthesia for poor mobilisation in another patient, which was successful in improving range of movement. A further patient required arthroscopic trimming of the cartilage graft which had overgrown; this was also successful.

Conclusion: Symptomatic cartilage defects and ACL deficiency may co-exist in many patients and represent a treatment challenge. Our early results suggest that a combined ACL and ACI repair is a viable option in this group of patients and should reduce the anaesthetic and operative risks of a two-stage repair. More patients and longer follow up will be required to fully assess this technique.

Avascular necrosis is a serious complication of slipped capital femoral epiphysis and is difficult to treat. The reported incidence varies from 3% to 47% of patients. The aims of treatment are to maintain the range of movement of the hip and to prevent collapse of the femoral head. At present there are no clear guidelines for the management of this condition and treatment can be difficult and unrewarding.

We have used examination under anaesthesia and dynamic arthrography to investigate avascular necrosis and to determine the appropriate method of treatment. We present 20 consecutive cases of avascular necrosis in patients presenting with slipped capital femoral epiphysis and describe the results of treatment with a mean follow-up of over eight years (71 to 121 months). In patients who were suitable for joint preservation (14), we report a ten-year survivorship of the hip joint of 75% and a mean Harris hip score of 82 (44 to 98).

Introduction: Avascular necrosis (AVN) is a devastating complication of slipped capital femoral epiphysis (SCFE) and is difficult to treat. The incidence of AVN in this condition varies considerably and is reported to appear in 3–47% of patients. The aims of the treatment of AVN are to maintain range of movement of the hip whilst preventing collapse of the femoral head. Clear treatment guidelines of this condition do not currently exist and the treatment of this condition can be difficult and unrewarding.

Method: Dynamic arthrograms were used to assess of cases of AVN in order to determine the method of treatment. We present 20 sequential cases of AVN in patients presenting to our unit with SCFE and report the long-term results of treatment with a mean follow-up in excess of 10 years.

Results: In 100 consecutive cases of SUFE there were 20 cases of AVN. There were 18 cases of salvage surgery and one patient refused surgery. Of the 18, there were 2 acetabuloplasty procedures, 12 proximal valgus osteotomies and 4 arthrodeses. At a later date there were 3 proximal femoral osteotomies and 5 total hip replacements.

Discussion: There is a good functional result in the majority of cases and a logical approach delays the need of total hip replacement in the majority of cases. The management depends on the radiography, the arthogram and the EUA. If there is early AVN with no collapse the treatment is a shelf procedure. If there is hinge abduction the treatment is a valgus femoral osteotomy. If there is instable movement and the hip is not congruent the treatment is hip arthrodesis.

When managing malignant bone tumours in the distal femur with limb salvage, resection and reconstruction with a distal femoral replacement (DFR) conventionally entails prosthetic replacement of the knee joint. In younger patients it is desirable to try to preserve the knee joint. We now use a new Joint-Sparing distal femoral prosthesis in those cases where it is possible to resect the tumour and preserve the femoral condyles. Purpose of study: To look at our early results with knee joint preserving DFR’s. Methods: Between June 2001 and March 2004 the prosthesis was implanted in 8 patients (5 males and 3 females) aged between 8 and 24 years at the time of surgery. The diagnosis was osteosarcoma in 6 cases and chondrosarcoma in 2 cases. All patients were followed regularly and knee range of movement was recorded as well as any complications that occurred. Patients were functionally evaluated using the MSTS Scoring System. Results: Six of the patients had a mean follow-up of 20 months (range 8–33) and in this group 4 had good knee flexion with a mean flexion of 122° (110–130), 1 patient had fair flexion of 60° and 1 patient had poor flexion of 20°. The mean fixed flexion deformity in the 3 patients who had such a deformity was 10° (5–15). There were no intraoperative complications but the patient with poor flexion required an arthrolysis and because of the poor result is under consideration for conversion to a conventional DFR. Two patients had follow-up periods of 3 months or less and are still in their early rehabilitation period. One patient in this group developed sepsis that resolved after an open washout. Conclusions: Our early results with this prosthesis, in the patients with adequate follow-up, have been good in the majority but the two cases of fair and poor knee flexion are disappointing. This particular problem may relate to design and technical factors, which will be discussed in detail.

When managing malignant long bone tumours in skeletally immature patients it is desirable, after resection, to reconstruct with a prosthesis that can be lengthened at appropriate intervals to keep pace with growth of the contralateral side. In an attempt to avoid multiple surgical procedures to achieve such lengthening we have recently developed a prosthesis that can be lengthened non-invasively.

Purpose of study: To look at our early experience with the use of non-invasive growing femoral prostheses.

Methods: Between November 2002 and February 2004 the prosthesis was implanted in 6 patients (3 males and 3 females) with a diagnosis of osteosarcoma. The patients were aged between 9 and 14 years (mean 11.5 years) at the time of surgery. Patients were lengthened at appropriate intervals and the process was monitored with scanograms. The prosthesis contains a magnet that is connected to gears that drive the extending mechanism. The patients’ limb is placed into a coil and the principle of electromagnetic induction coupling is used to achieve lengthening. Total degree of lengthening to date was recorded for each patient together with the range of knee movement and any complications that occurred. Patients were functionally evaluated at their last follow-up visit using the Musculoskeletal Tumour Society (MSTS) Scoring System.

Results: To date patients have been lengthened by an average of 18mm (8–48mm). The mean amount of knee flexion is 125 degrees. The mean MSTS score is 18 (16–21). There have been two complications; one patient developed patella subluxation during the lengthening programme and one patient has required serial casting to treat a flexion deformity of 25 degrees.

Conclusions: We have been encouraged by our early results with this prosthesis and have been able to demonstrate that the technology works reliably in vivo. We are continuing to use this prosthesis in skeletally immature patients.

Aims: To compare incidence of abductor dysfunction using two direct lateral approaches, a more conventional approach and a new modified approach that reliably identifies and separately detaches gluteus minimus from the greater trochanter to allow its subsequent secure repair. Methods: We followed-up 73 patients who had undergone total hip arthroplasty by a single senior surgeon using one of two direct lateral approaches. With the more conventional approach (33 patients) medius and minimus were not reliable detached separately from the trochanter; minimus was either detached en mass with the anterior half of medius or detached during capsulotomy/capsulectomy. The new modified approach (40 patients), developed after careful study of the anatomy of the attachments of the glutei, involved division of the anterior half of medius leaving a 1 cm cuff of tissue attached to the trochanter and allowed reliable identification and separate detachment of minimus. Stay sutures were used in a novel way to achieve a more secure reattachment to try and reduce the risk of failure of the repair. Abductor function was assessed by Trendelenberg testing at 1-year post-arthroplasty. Results: The incidence of abductor dysfunction was 12% with the more conventional approach and 2.5% with the new modified approach. Conclusions: A significantly reduced incidence of abductor dysfunction occurred with our new modified approach and we believe this provides evidence for the importance of separate identification of gluteus minimus and its careful reattachment in ensuring good abductor function.

To study the outcome of stabilisation of humeral shaft fractures using an elastic retrograde humeral nail that is self-locking proximally and easily locked distally.

20 closed humeral shaft fractures were stabilised in 19 patients between 1996 and 1999.

There were three acute fractures, nine cases of failed non-operative treatment (three cases of loss of fracture position and six cases of non-union), five established pathological fractures and three impending pathological fractures. The average age of the patients in the acute/failed non-operative treatment group was 43. 6 years (range 18 to 83 years) and in the established/impending pathological fracture group was 73. 6 years (range 60 to 81 years).

Patients in the acute/failed non-operative treatment group were followed until fracture union. This occurred without further intervention in 83% of cases at a mean of 11. 8 weeks (range 10 to 16 weeks). Shoulder and elbow movement were rated by determining the percentage loss of movement compared to the other side. Almost all these patients regained a full range of elbow and shoulder movement without residual pain or disability. Two cases needed further surgery to achieve union and it was noted that nail removal in these patients was difficult. In one of these cases the original injury was a floating elbow. All of the pathological fractures were successfully stabilised with good pain relief. Four of the five patients with established fractures survived to fracture union. This occurred at a mean of 12. 5 weeks (range 10 to 16 weeks) without the need for further procedures. There were few complications.

We have obtained encouraging results with both pathological and non-pathological fractures using this nail with good preservation of both shoulder and elbow movement. We have continued to use the nail routinely.