We prospectively reviewed 2440 Cemented Anantomical (side specific) AGC total knee replacements performed on 2074 patients between 2002 and 2008 in our unit. The surgery was performed by a number of surgeons, both Consultant and Trainee grades. 1357 underwent PCL sacrificing surgery with implantation of Posterior Stabilised Femoral Implant (Cam and Grove) and 1083 underwent PCL retaining surgery with implantation of a Non-Stabilised Femoral Implant. The mean age at date of surgery for Posterior Stabilised prosthesis was 69 years (range 23-94) and Non-Posterior Stabilised prosthesis was 70 (range 33-97) with no significant difference p< 0.05 (C.I 95%). Follow up at present mean 4 years (range 1-6 years). 11 patients underwent secondary patella resurfaced for anterior knee pain at a mean of 1.5 years following the index procedure (range 0.5-4.1 years) with 6 patients reporting a marked improvement in anterior knee pain post operatively. 3 patients underwent removal of patella buttons for symptomatic loosening at a mean of 2.7 years follow index procedure. A total of 17 patients underwent a revision of either tibial or femoral components (0.7%). Indications for revision were infection in 11 patients, gross instability in 1 patient, periprosthetic fracture in 1 patient, persistent stiffness in 1 patient. 3 patients underwent revision for symptomatic loosening of the tibial component at a mean of 2.9 years (range 1.1-4.0). These short to medium term results for the Anatomic AGC total knee replacement agree with published results from other centres.
We performed a retrospective review of 98 patients with malignant tumours of the periacetabular region, treated by resection and endoprosthetic reconstruction between 1971 and 2005 at the Royal National Orthopaedic Hospital, Stanmore and The Royal Orthopaedic Hospital, Birmingham. The mean age of the patients was 43.6 years (10 to 76). 53 patients (54%) were male. The age distribution demonstrated peaks in the 2nd and 6th decades. The mean follow up was 65 months (2 to 405. The overall 10-year survival rate was 56% (determined by the Kaplan-Meier method). 54 patients (58.1%) had one or more complications. Infection was the most common (30%) with the majority occurring in the first 2 years. Dislocation occurred in 19 (20%) of our patients all in the first year following surgery. All were recurrent with a mean of 2.9 (2 to 6) episodes. Operations performed before 1994 were associated with a dislocation rate of 40.5% and after 1996 the rate was only 3.9% (p < 0.001). Function was assessed according the Toronto Extremity Salvage Sore (TESS). The overall TESS was 59.4. In patients that had a major complication the TESS was 37.1 but in the group that did not the TESS was 70.3 (p < 0.001). Men experienced higher rates of death, infection and revision than women (p < 0.05). The local recurrence rate was 31% with high grade tumours associated with higher recurrence rates (p < 0.05). Tumour resection in the ilium is associated with higher rates of infection than tumours located in the periacetabular region alone (p < 0.05). This method of reconstruction is still associated with high complication rates. Function is good if a major complication can be avoided. The lower dislocation rate more recently is probably the result of improved surgical technique and the use of larger femoral heads.
We have investigated whether improvements in design have altered the outcome for patients undergoing endoprosthetic replacement of the distal femur following tumour resection. Survival of the implant and ‘servicing’ procedures have been documented using a prospective database and review of the implant design records and case records. A total of 335 patients underwent a distal femoral replacement with 162 having a fixed hinge design and 173 a rotating hinge with most of the latter group having a hydroxyapatite collar at the bone prosthesis junction. The median age of the patients was 24 years (range 13-82 yrs). With a minimum follow up of 5 years and a maximum of 30 years, 192 patients remain alive with a median follow-up of 11 years. The risk of revision for any reason was 17% at 5 years, 34% at 10 years and 58% at 20 years. One in ten patients developed an infection and 42% of these patients eventually required an amputation. Aseptic loosening was the most common reason for revision in the fixed hinge knees whilst infection and stem fracture were the most common reason in the rotating hinges. The risk of revision for aseptic loosening in the fixed hinges was 32% at ten years compared with nil for the rotating hinge knees with a hydroxyapatite collar. The overall risk of revision for any reason was halved by use of the rotating hinge, and for patients older than 40 years at time of implant. Improvements in design of distal femoral replacements have significantly decreased the risk of revision surgery. Infection remains a serious problem for these patients.Conclusion
EPRs are the treatment of choice following resection of tumours. These have been used for 39 years in our institution. There has been concern regarding the long term survival of endoprosthesis; this study investigates the fate of the reconstruction. Between 1966 and 1995, 3716 patients were seen with a suspected neoplasm and 776 patients underwent EPRs. Patients receiving growing endoprostheses were excluded from the study as they invariably require revision, leaving 667 replacements. Insufficient data was available in 6 cases, leaving 661 patients in the study group. Information was reviewed concerning the diagnosis, survival of implant and patient, subsequent surgery, complications and functional outcome. Kaplan-Meier survival analysis was used for implant survival with end points defined as revision for mechanical failure (aseptic loosening, implant fracture, instability, avascular necrosis, periprosthetic fracture, pain and stiffness) and revision for any cause (infection, local recurrence and mechanical failure). Mean age at diagnosis was 34 years. Overall patient survival was 52.7% at 10 years and 45.7% at 20 years. The mean follow-up for all patients was 9 years, and for those patients who survived their original disease, the mean follow-up was 15 years. 227 (34%) patients underwent revision surgery, 75 patients for infection (33%), 36 patients for locally recurrent disease (16%) and mechanical failure in 116 patients (51%). With revision for mechanical failure as the end-point, implant survival was 75% at 10 years and 52% at 20 years. With revision any cause as an end-point implant survival was 58% at 10 years and 38% at 20 years. Overall limb salvage was maintained in 91% of patients at 10 years from reconstruction and 79% at 20 years. There was a significant difference between survival of implant between implantation sites, with the proximal humeral implant survival being the best and tibial reconstructions being the worst. The MTSS functional score was available on 151 patients, with a mean score of 25/30 (83%) at last follow-up visit.Methods
Results
Chondroblastomas arise in the epiphyseal area of bones. In the femoral head this can cause considerable difficulty in obtaining access as the epiphysis is entirely intra-articular. We have reviewed management and outcome of 10 patients with chondroblastoma of the femoral head to identify outcome and complications. The mean age was 14 years and all presented with pain (frequently in the knee) and a limp. All were diagnosed on plain Xray and MRI. Five younger children were treated by curettage by a lateral approach up the femoral neck (to try and minimise damage to the epiphysis) and five by a direct approach through the joint. Two of the five patients with a lateral approach developed local recurrence whilst none of the direct approaches did. Both local recurrences were cured with a direct curettage. One patient developed overlengthening of the leg by 1cm but there was no case of growth arrest or osteoarthritis. We recommend a direct approach to the lesion whenever possible to give the best chance of cure with a low risk of complications.
Despite the advances in adjuvant chemotherapy and surgical techniques, the diagnosis of a bone tumour still carries with it a significant risk of mortality. This study investigates factors affecting survival, in patients treated for malignant tumours of bone using Endoprosthetic replacement (EPR). Our tertiary referral musculoskeletal tumour unit has taken referrals over 40 years. Electronic patient records have been prospectively kept on all patients seen since 1986 and data has been entered retrospectively for patients seen between 1966 and 1986. A consecutive series of 1264 patients underwent endoprosthetic reconstruction; after 158 patients were excluded, 1106 patients were left in the study group. Factors including diagnosis, size of tumour, surgical margins, percentage tumour necrosis following chemotherapy, tumour site, local recurrence, decade of reconstruction, fracture and post-operative deep infection were analysed.Introduction
Methods
To identify patient, tumour or treatment factors that influence outcome in patients with radiation induced sarcoma of bone. A retrospective review of an oncology database supplemented by referral back to original records.Aim
Method
Primary malignant bone tumours frequently arise in children close to the knee, hip or shoulder. Resection of the tumour will often require excision of the epiphysis and frequently one side of the involved joint. In these children an extendable endoprosthesis is usually required to allow for maintenance of limb length equality. We have used 180 extendable endoprostheses in 176 children since 1975. The indication for use of an extendable prosthesis was if there was more than 30mm of growth remaining in the resected bone. The age of the patients ranged from 2 to 15 and 99 were boys. The sites of the endoprostheses used were: distal femur in 91, proximal tibia in 42, proximal femur in 11, total femur in 6 and proximal or total humerus in 26. 131 of the operations were for osteosarcoma and 34 for Ewing's. Five types of lengthening mechanism have been used. Two designs used a worm screw gear, one type used a C collar, one type a ball bearing mechanism and the latest uses a non invasive lengthening system whereby a motor inside the prosthesis is activated by an electromagnetic field. Of the 176 patients, 59 have died and of the remainder, 89 have reached skeletal maturity. 19 patients had an amputation, 11 due to local recurrence and 8 due to infection. The risk of infection was 19% in surviving patients. Most of the skeletally mature had equal leg lengths. The average number of operations was 11 but ranged between 2 and 29. Most operations were for lengthening but younger children always needed revisions of the prosthesis. Functional scores were 77%. Extendable endoprostheses are demanding both for the patient and the surgeon. The high complication rate should be decreased by non invasive lengthening prostheses.
All patients referred to our unit with previously untreated metastatic renal cancer were included in this review. We investigated likely prognostic factors including age, sex, site, synchronous or metachronous metastasis, stage of the disease and the type of treatment received. From 1976 until 2004, a total of 198 patients were treated by our unit for renal metastases. 15 patients were excluded because they were referred after failure of previous treatment or only had advice. 96 patients were already known to have renal metastasis with their diagnosis having been made between 0.2 and 17 years from the diagnosis of primary cancer (mean 4 years). 33 patients presented to us with a pathological fracture and were found to have renal cancer. A total of 54 patients had multiple metastases and 129 had a solitary metastasis. The cumulative survival from the time of diagnosis of the bone metastasis is 70 percent at 1 year, 40% at 3 years and 18% at 5 years. In patients with a solitary metastasis, the overall survival was 74% at 1 year and 45% at 3 years, whereas in patients with multiple metastases it was 55% at 1 year and 22% at 3 years. (p=0.02) In patients with a solitary metastasis treated by excision of the metastasis, the survival at 1 year was 86% as compared to 38% for those that were treated with just a local procedure. Cox multivariate analysis shows that survival was better in those with solitary metachronus metastasis who underwent a radical procedure. We recommend a radical procedure for patients who present with a solitary renal metastasis, particularly those with a disease-free interval of more than one year.Conclusion
For the bilaterally normal group the mean hip rotation was 2.9 degrees internal (SD 11.8). For the arthroplasty group the mean rotation on the normal and operated sides were 9.4 degrees external (SD 9.5) and 6.9 degrees internal (SD 13.9) respectively. In this group there was a significant difference between the normal and operated side (P= 0.02).
An electromagnetic tracking system was used to measure the flexion in the operated and normal hip of each patient. Tracker sensors were placed on the iliac crest and the mid-lateral thigh. The patients were then asked to flex forward from a standing position to pick an object up off the floor. This movement was repeated 3 times. Flexion data was collected at 10Hz which was accurate to 0.15 degrees. Spinal flexion was not recorded during the task. Patients were also asked to complete the Harris and Oxford Hip Score questionnaires to obtain qualitative data regarding their hip replacement.
Small bearing group:
Operated side: Peak flexion = 79.3 Normal side: Peak flexion = 83.4. Thus the bilateral difference for peak flexion was 4.1 (paired t-test, P=0.12). Large bearing group: Operated side: Peak Flexion = 72.7. Normal side: Peak Flexion = 74.0 Thus the bilateral difference for peak flexion was 1.3 (paired t-test, P= 0.83). Comparing the small bearing group with the large bearing group, the peak difference was 6.6. This difference was non-significant with P = 0.43. All patients reported good – excellent functional results when completing the Harris and Oxford Hip Scores.
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.
Of 3000 patients diagnosed with primary malignant bone tumours and treated at our unit over the past 25 years, 234 (7.8%) were considered to be spindle cell sarcomas of bone (ie not osteosarcoma, chondrosarcoma, Ewing’s, chordoma or adamantinoma). We have analyzed their management and outcomes. The diagnosis of these cases varied with fluctuations in the popularity of conditions such as MFH, fibrosarcoma and leiomyosarcoma with the passage of time. Treatment was with chemotherapy and surgery whenever possible. 36 patients had metastases at diagnosis and 17 had palliative treatment only because of age or infirmity. The most common site was the femur followed by the tibia, pelvis and humerus. The mean age was 45 and the mean tumour size 10.2cm at diagnosis. 25% of patients presented with a pathological fracture. Chemotherapy was used in 70% of patients the most common regime being cisplatin and doxorubicin. 35% of patients having neoadjuvant chemotherapy had a good (>
90% necrosis) response. The amputation rate was 22% and was higher in patients presenting with a fracture and in older patients not having chemotherapy. With a mean follow up of 8 years the overall survival was 64% at 5 yrs and 58% at 10 yrs. Adverse prognostic factors included the need for amputation, older age and poor response to chemotherapy as well as a pathological fracture at presentation. The few patients with angiosarcoma fared badly but there was no difference in outcomes between patients with other diagnoses. We conclude that patients with spindle cell sarcomas should be treated similarly to patients with osteosarcoma and can expect comparable outcomes. The histological diagnosis does not appear to predict behaviour.
The overall patient survival was 69% at 5 years and 62% at 10 years. Local recurrence arose in 4 cases, 3 of whom already had metastatic disease. None of the LR arose in the irradiated bone. The rate of non union was 9% at the 58 osteotomies, the greatest risk being in the tibia. There were four graft fractures of which 3 needed fixation and all united. There is one case of convincing graft resorbtion after 12 years. Two patients developed infections but there have been none since the done was routinely immersed in antibiotics whilst being irradiated.
The two week wait has been established as a potential means of diagnosing malignant tumors earlier and thus hopefully leading to improvements in outcome. There remains controversy as to whether these clinic achieve this end or whether they just speed up treatment of patients already diagnosed (eg by imaging)
The purpose of our study was to examine the survival and functional outcome of endoprosthetic replacements for non-oncology limb salvage purposes. Although initially designed for bone tumours, such is the versatility of these implants they can be used to salvage failed joint replacements, peri-prosthetic fractures, failed internal fixation and non-union. Thirty eight procedures were identified from September 1995 to June 2007 from a prospectively kept database, including 17 distal femoral replacements, 12 proximal femoral replacements, 4 proximal humeral replacements, 2 distal humeral replacements, 2 hemi-pelvic replacements and 1 total femoral replacement. The quality of patients’ mobility was used to assess functional outcome and the survival of the prosthesis was calculated using a Kaplan-Meier survival curve. The Kaplan-Meier implant survival was 91.3% at 5 years, 68.5% at 10 years and 45.7% at 20 years. The limb salvage survival for all reconstructions was 75% at 10 years. The best survival was as follows pelvic (n=0/2) and total femoral prostheses where there was no failure in either group (n=0/1). Distal femoral replacements survival was 91% at 5 years, a single humeral prosthesis failed at 11 years post surgery, and proximal femoral replacements had a survival at 87.5% at 5 years. Three implants failed, two as a result of infection and required staged revisions and 1 failed as a result of aseptic loosening. Two patients dislocated their proximal femoral replacements, both were treated successfully by closed reduction. Endoprosthetic replacement appears to be effective and the medium term survival is encouraging. The aim of a pain free functional limb is achievable with this technique. The complication rates are acceptable considering the salvage nature of these patients. We recommend referral of complex cases to a tertiary centre with expertise in this type of surgery.
Endoprosthetic replacement of the pelvis is one of the most challenging types of limb salvage surgery with a high rate of complications. In order to try and decrease the high risk of complications and to allow greater versatility in the reconstruction options, a new concept of pelvic endoprosthesis was developed in 2003. Since then 20 of these ice cream cone pelvic prostheses have been inserted at our centre incorporating antibiotic laden cement around the prosthesis to minimize infection risk.