Non-invasive expandable prostheses for limb salvage tumour surgery were first used in 2002. These implants allow ongoing lengthening of the operated limb to maintain limb-length equality and function while avoiding unnecessary repeat surgeries and the phenomenon of anniversary operations. A large series of skeletally immature patients have been treated with these implants at the two leading orthopaedic oncology centres in England (Royal National Orthopaedic Hospital, Stanmore, and Royal Orthopaedic Hospital, Birmingham). An up to date review of these patients has been made, documenting the relevant diagnoses, sites of tumour and types of implant used. 87 patients were assessed, with an age range of 5 to 17 years and follow up range of up to 88 months. Primary diagnosis was osteosarcoma, followed by Ewing's sarcoma. We implanted distal femoral, proximal femoral, total femoral and proximal tibial prostheses. All implants involving the knee joint used a rotating hinge knee. 6 implants reached maximum length and were revised. 8 implants had issues with lengthening but only 4 of these were identified as being due to failure of the lengthening mechanism and were revised successfully. Deep infection was limited to 5% of patients. Overall satisfaction was high with the patients avoiding operative lengthening and tolerating the non-invasive lengthenings well. Combined with satisfactory survivorship and functional outcome, we commend its use in the immature population of long bone tumour cases.
There is limited literature available on the use of metal prosthetic replacements for the treatment of non-traumatic lesions of the proximal radius. This study discusses the implant survivorship and the functional outcome of the elbow following insertion of metal proximal radius endoprostheses performed at the Royal National Orthopaedic Hospital. We present a series of six patients treated with endoprosthetic reconstruction of the proximal radius following resection of non-traumatic pathologies. The patients included four females and two males, with a mean age of 39 years at the time of surgery. Their diagnoses included Ewing’s sarcoma, chondroblastoma, benign fibrous histiocytoma, radio-ulna synostosis and renal carcinoma metastases in two patients. Follow-up extended to 192 months with a mean of 76 months. During this time there were no complications with the prostheses, the most recent radiographs demonstrated secure fixation of the implants and none required revision. One patient developed posterior interosseuous nerve neuropraxia following surgery, which partially recovered, and another patient passed away as a result of disseminated metastatic renal cell carcinoma which was present preoperatively. The patient with radio-ulna synostosis had a 25° fixed flexion deformity of the elbow post-operatively but good flexion, supination and pronation. All other patients had full ranges of movement at the elbow. Functional scores were assessed using the Mayo Elbow Performance Score with patients achieving a mean score of 86 out of 100. The results of the use of proximal radial endoprostheses for treatment of non-traumatic lesions are encouraging with regards to survivorship of the implant and functional outcome of the elbow.
Metal-on-metal arthroplasties are being inserted in increasing numbers of younger patients due to the increased durability and reduced requirement for revision in these implants. Recent studies have raised many concerns over possible genotoxicity of MoM implants. This is a prospective study of patients who have undergone elective total hip replacement, they were selected and then randomised into two groups. Group A received a MoP implant and group B received a MoM implant. Patients are reviewed pre-operatively (control group), at 3 months, 6 months, 1 year and 2 years post-operatively. On each occasion blood tests are taken to quantify metal ion levels (chromium, cobalt, titanium, nickel and vanadium) using HR-ICPMS method and chromosome aberrations in T lymphocytes using 24 colour fluorescent in situ hybridisation (FISH). Fiffty three patients have been recruited to date, 24 of whom had MoP prosthesis and 29 a MoM. 25 of these have had their one-year follow-up with blood analysis. Cobalt and chromium concentration increased during the first 6 months in both MoM and MoP groups, in the MoM group the chromium levels were twice that of MoP group and 12x that of the preoperative samples. There was no difference with the levels of titanium, nickel and vanadium. Chromosome aberrations occurred in both groups. At 6 months both the MoM and MoP groups showed increase frequency of aneuploidy aberrations with further increases after one year. Structural damage in the form of translocations occurred in the MoM group after one year, but not in the MoP group. Preliminary results of this study show that the levels of chromium and cobalt are significantly higher in the MoM group compared to the MoP group. This corresponds to increases in chromosome aberrations between the groups particularly in translocations present in the MoM group at 1 year.
High Tibial Osteotomy (HTO) is a recognised method of correction for knee joint malalignment and unicom-partmental osteoarthritis. Long-term results of this technique have been reported and are favourable. Good results have also been reported with Autologous Chondrocyte Implantation (ACI-C, MACI). Malalignment, if present, should be corrected when ACI is performed. Although results have been reported for either procedure separately, the outcomes of combined HTO-ACI remain unreported. The aim of this study was to evaluate functional outcome in patients undergoing combined HTO-ACI procedures. Twenty three patients undergoing a combined ACI-HTO procedure were identified retrospectively from a larger trial of patients undergoing ACI for symptomatic chondral defects. The mean age of the patients was 36 (28 – 49). The mean follow-up was 54 months (12 – 108) and mean defect size was 689mm2 (range 350 – 1200). Nine patients had ACI-C and HTO, the remainder having MACI and HTO. Pre and post-operative assessment was carried out using the Visual Analogue Score (VAS), the Bentley Functional Rating Score and the Modified Cincinnati Rating System. The Mean VAS score improved from 7.4 (4 – 10) pre-operatively to 2.9 (0 – 6) post-operatively at the latest follow-up (p<
0.0001). The Bentley Functional Rating Score improved from 2.9 (2 – 4) to 1.8 (0 – 4), which was statistically significant (p<
0.0001). The Modified Cincinnati Rating System improved from 35.2 (20 – 49) pre-operatively to 68.7 (46 – 85) post-operatively (p<
0.0001). Fourteen patients underwent biopsy of the graft site at a mean of 13.7 months: 21% of biopsies were hyaline-like cartilage, 36% were mixed hyaline/fibrocartilage, 29 % were fibrocartilage and 14% were fibrous tissue. Combining high tibial osteotomy with autologous chondrocyte implantation is an effective method of decreasing pain and increasing function in the short term. Further evaluation of this procedure is required.
Non-invasive expandable prostheses for limb salvage tumour surgery were first used in 2002. These implants allow ongoing lengthening of the operated limb to maintain limb-length equality and function while avoiding unnecessary repeat surgeries and the phenomenon of anniversary operations. A large series of skeletally immature patients have been treated with these implants at the two leading orthopaedic oncology centres in England (Royal National Orthopaedic Hospital, Stanmore, and Royal Orthopaedic Hospital, Birmingham). An up to date review of these patients has been made, documenting the relevant diagnoses, sites of tumour and types of implant used. 74 patients were assessed, with an age range of 7 – 16 years and follow up range of 4 – 88 months. We identified five problems with lengthening. One was due to soft tissue restriction which resolved following excision of the hindering tissue. Another was due to autoclaving of the prosthesis prior to insertion and this patient, along with two others, all had successful further surgery to replace the gearbox. Another six patients required mechanism revision when the prosthesis had reached its maximal length. Complications included one fracture of the prosthesis that was revised successfully and six cases of metalwork infection (two of which were present prior to insertion of the implant and three of which were treated successfully with silver-coated implants). There were no cases of aseptic loosening. Overall satisfaction was high with the patients avoiding operative lengthening and tolerating the non-invasive lengthenings well. Combined with satisfactory survivorship and functional outcome, we commend its use in the immature population of long bone tumour cases.
Large head metal-on-metal articulating surfaces of the hip are being used in increasing numbers of patients for oncological purposes due to the increased stability and reduced dislocation rate. Recent studies have raised many concerns over possible genotoxicity of MoM implants.
We have reviewed five adult patients treated with endoprosthetic reconstruction of the proximal radius following resection of non-traumatic lesions. The patients had a mean age of 33.4 years (20 to 60) at the time of surgery and the mean follow-up was 7.6 years (0.8 to 16). Following surgery, all elbows were clinically stable and there was 100% survivorship of the prosthesis. Evaluation of function was assessed clinically and by the Mayo Elbow Performance Score, achieving a mean of 86% (70 to 100). Results at medium-term follow-up are encouraging with regards to elbow stability, implant survivorship and functional outcome.
This case highlights the close association between osteo-fibrous dysplasia (OFD) and adamantinoma, drawing attention to the role for more radical treatment options when treating OFD. We discuss the advancements in joint-sparing endoprostheses using bicortical fixation. Finally we describe a unique biomedical design allowing for manufacture of an end cap to allow amputation through a custom made joint-sparing proximal tibial replacement as opposed to an above knee amputation. A 37 year old presented 7 years ago having sustained a pathological fracture of her tibia. Subsequent biopsy revealed OFD, curettage with bone graft was performed. She later developed recurrence, two percutaneous biopsies confirmed OFD. 6 years following her initial diagnosis she was referred to RNOH with further recurrence, a biopsy at this stage revealed a de-differentiated adamantinoma. A joint-sparing proximal tibial replacement was performed and adjuvant chemotherapy administered, she remained well for one year. Recurrence was noted at the distal bone-prosthesis interface, histology revealed a high grade dedifferentiated osteosarcoma, limb preservation was not deemed possible and an amputation was performed through the prosthesis. The proximal tibial device was uncoupled leaving a residual 7 cms insitu, a small custom made end cap was attached to the remaining prosthesis and a myocutaneous flap fashioned over it, this ultimately enabled the patient to mobilise well with a below–knee orthotic device. This case highlights the need for more radical surgery when treating cases of OFD and the relationship between OFD and adamantinoma. It also introduces a joint-sparing proximal tibial device for use in proximal tibial tumours that do not invade the proximal tibial metaphysis. The biomechanical design solution has given us the unique option of preserving the knee joint allowing the patient a below knee amputation whereas previously an above knee amputation would have been performed thereby significantly reducing her functional outcome.
Elastofibroma dorsi is a rare, benign, slow-growing ‘pseudotumour’ classically presenting as an ill defined mass at the inferior pole of the scapula. Typical symptoms include mass, pain, scapular snapping and impingement like features. There is a predilection for females after the fifth decade of life. The aetiology is unclear. We identified 15 patients (21 tumours) with a diagnosis of elastofibroma. Seven lesions were found on the left side and fourteen on the right; bilateral lesions were found in six patients. The male:female ratio was eight:seven and mean age at presentation was 60.9 years (range 40 – 71). The mean duration of symptoms (most commonly pain, mass and scapular snapping) prior to presentation was 25.8 months. Eighteen tumours were excised with a mean follow-up of 4.2 years (0.25–16). Four lesions were diagnosed by combined MRI and CT guided biopsy, the remainder identified using MRI alone. All patients were asked specifically about symptoms, occupation, family history and employment history (including hobbies). Pain was assessed using the Visual Analogue Score (VAS) and functional outcome using the Stanmore Percentage of Normal Shoulder Assessment (SPONSA) Score. Range of forward flexion of the shoulder joint was also assessed. In the operative group, the mean VAS score improved from 4.6 (0–10) pre-operatively to 2.5 (0–8) post-operatively. Mean SPONSA scores improved from 61.5% (20 – 100) to 81.8% (30 – 100). Mean pre-operative forward flexion was 135 degrees (70 – 180), this improved to 166 degrees (100 – 180) post-operatively. A high number of patients had been involved in occupations involving heavy lifting. MRI had a 100% sensitivity in identifying elastofibroma when correlated with histopathological evaluation. This series demonstrates that elastofibroma may be reliably diagnosed using MRI alone and, in the symptomatic patient, pain and function may be improved through operative excision.
Primary solitary fibrous tumour (SFT) of bone is extremely rare with few cases reported in the literature. The incidence of the lesion is 0.08% of all primary bone tumours (0.1% of primary malignant bone neoplasms). Previously, such lesions may have been reported as haemangiopericytoma (HP). Despite being previously considered as separate entities, the two types of tumour (SFT and HP) are now generally accepted as related, sharing similar morphological and immunohistochemical features. Cytogenetic and molecular analysis has, so far, been unable to unite or divide the two. Although frequently having a histologically benign appearance or being labelled as intermediate grade, these tumours may exhibit an unpredictable clinical course and behave in an aggressive manner. We present two cases of osseous solitary fibrous tumour (cellular haemangiopericytoma). Using the histopathology and bone tumour databases at our institution, we identified two patients (one female aged 21 and one male aged 40) with a histopathological diagnosis of osseous SFT. The site of primary tumour in both patients was the sacrum. In the female patient, the lesion was confined to the sacrum and she underwent curettage. In the male patient, the tumour extended beyond the sacrum to the sacro-iliac joint, ilium and gluteal mass, therefore, total sacrectomy was performed. At presentation neither patient had evidence of metastatic spread. The female patient was disease free at four years with no evidence of recurrence of metastases. The male patient developed metastases in both lung fields and bone (ribs, vertebrae) three years post-operatively and died four years post-operatively. Orthopaedic surgeons and histopathologists should remain aware of SFT due to its erratic behaviour and the recent move towards unifying it with HP in a continuous spectrum. We recommend early staging and treatment of these tumours, even for histologically benign/low grade lesions, due to their potentially aggressive behaviour.
Following resection of tumours in the distal femur, reconstruction with joint-sparing prostheses have shown good short-term functional outcomes. There is however limited literature on the affect of knee-sparing prostheses on function of the distal femoral physis in children of bone growing age. We discuss two patients, a male (11yrs) and female (10yrs) who had joint-sparing distal femoral prostheses inserted for treatment of Ewing’s sarcoma. The knee joint, along with the distal growth plate, was preserved and fixed to the distal end of the prosthesis using uni-cortical screws positioned distal to the physis. In the female, these screws were removed 6 months postop due to prominence of the screws under the skin. In both patients, we assessed radiographs from immediately post[surgery and the most recent follow-up (20 and 28 months respectively). In each set, for the operated limb, we measured the height and width of the distal femoral epiphysis, the total length of the femur and the length of the proximal femoral bone segment from the femoral head to the proximal bone-prosthesis interface. In addition, postoperative assessments of leg lengths, bilaterally, were documented. In both patients, distal femoral epiphyseal height and width in the operated leg showed no significant change following endoprosthetic replacement. In the female, growth did not resume even after removal of the epiphyseal screws. In both patients, lengths of the femur and the proximal bone segment increased significantly following surgery. The patients demonstrated no clinical leg length discrepancy at the most recent follow-up. This study suggests that the function of the distal femoral growth plate ceases following insertion of joint-sparing distal femoral endoprostheses, probably due to trans-physeal fixation. This does not appear to resume following early removal of distal screws. The proximal growth plate, however, continues to function adequately enough to maintain symmetry in overall leg length.
The proximal tibia is the second most common site for primary bone tumours. As a result of simultaneous advances in chemotherapy, surgical and biomechanical techniques limb salvage is now a practical option. We report the clinical and functional outcomes of eight patients who underwent limb salvage with a new form of endoprosthetic proximal tibial replacement that allows preservation of the knee joint. A retrospective, case series of 8 patients who underwent joint sparing proximal tibial replacement between 2004 and 2008. There were 2 males and 6 females with a mean age of 28.9 years (8–43) with overall mean follow up of 35 months (4–48). Functional outcomes were assessed using the Musculoskeletal Tumour Society (MSTS) rating score and revised Oxford Knee Score (OKS) Five patients had osteosarcoma, one patient had malignant fibrous histiocytoma, another adamantinoma and the final patient had Ewing’s sarcoma. All patients had complete tumour excision, neoadjuvant chemotherapy and to date there have been no distant metastasis. One patient however required a below knee amputation through the prosthesis due to local recurrence at the distal bone/prosthesis interface. Another patient fell at postop day 8 and fractured through the tibial metaphyseal bone requiring ORIF; this healed in extension and ultimately required revision to a proximal tibial replacement 20 months later. Mean MSTS and OKS for the remaining 6 patients were 77% (57–90) and 40 (36–46) respectively. Limb salvage preserving the knee joint is an effective alternative to a proximal tibial replacement when the metaphyseal bone is tumour free. The joint sparing prosthesis has a favourable functional result when compared to the joint sacrificing prostheses. Retaining the native joint improves functional outcomes and reduces the peak loads through the prosthesis. There was no short-term evidence of loosening. Further follow up is required to ascertain the long-term outcomes of this new prosthesis.
