The aim of this study was to determine the torsional and 4-point bending properties of a midshaft humeral osteotomy reconstructed with either an intramedullary nail or locking plate.
A transverse midshaft osteotomy was created and a spacer ensured a constant 3-mm gap between the bone ends. Reconstruction was performed with either
Trigen humeral nail (Smith &
Nephew, TN) – 10 specimens Humeral locking plate (Synthes, PA) – 9 specimens Non-destructive 4-point bending was repeated, and then each humerus was embedded in a low-melting point alloy proximally and distally for torsional testing. Torque was applied at 5 deg/min until failure. Maximum torque, maximum angle and stiffness were calculated. All data were analysed with SPSS for Windows (SPSS Inc., Il) using ANOVA.
4-point bending: the bones reconstructed with the intramedullary nail were ~50% as stiff as the intact state in both planes. There was no statistically significant difference in stiffness between the intact bones and those reconstructed with the locking plate. Torsional testing: the locking plate specimens were 3 times as stiff as the intramedullary nail specimens (P<
0.05) and failed at twice the torque (P<
0.05).
Seven specimens were used for mechanical analysis. A humeral osteotomy was performed distal to the insertion of pectoralis major, leaving intact the biceps sheath and the muscle belly of long head of biceps. The proximal humerus was attached to a custom-designed jig and the muscle belly of biceps grasped in cryogenic grips. Specimens were loaded on an MTS 858 Bionix mechanical testing machine (MTS Systems, MN) in uniaxial tension at a rate of 1 mm/sec until failure was observed.
Histological examination of the biceps sheath revealed membranous tissue consisting of loose soft tissue with fat and blood vessels. Synovial tissue was also identified. The sheath was seen to loosely attach to the biceps tendon, with a more intimate attachment to the periosteum. The mean force to pull the long head of biceps tendon out of the sheath 102.7 N (range 17.4 N–227.6 N)
. There is less information on normal foetal hip . Magnetic resonance imaging (MRI) allows development to be followed in the healthy baby.
To establish normal patterns of hip development. To obtain charts that could be used to detect abnormality earlier. There are three aspects to this study:
Validation – analysing MRI scans of babies hips prior to post mortem (the gold standard) would verify MRI as a valid tool for such studies. Measurements will be gained for foetus in utero Similarly for pre and term babies.
For the initial validation process, parents who had consented to post mortem were asked to consider additionally an MR scan of their neonate’s hips, a total of 30 cases.
Measurements were made, by two independent observers, of the width and depth of the acetabulum and the radius &
diameter of the femoral head, volume and area were calculated. Inter-observer variation was assessed.
With the exception of the acetabular width each dimension showed little development until week 20 when the line of growth rose exponentially. The acetabular width showed only a slow rate of growth despite the changes seen in the femoral head. Levels of observer agreement were high (ICCs = 0.98) for all but depth (ICCs = 0.86). The measurements for all dimensions were in line with previous post mortem studies.
Considerable differences in kinematics between different designs of knee prostheses and compared to the natural knee have been seen in vivo. Most noticeably, lift off of the femoral condyles from the tibial insert has been observed in many patients. The aim of this study was to simulate lateral femoral condylar lift off in vitro and to compare the wear of fixed bearing knee prostheses with and without lift off. Twelve PFC Sigma cruciate retaining fixed bearing knees (DePuy, Leeds, UK) were tested using six station simulators (Prosim, Manchester, UK). The kinematic input conditions were femoral axis loading (maximum 2.6 kN), flexion-extension (0–58°), internal/external rotation (±5°) and anterior/posterior displacement (0–5 mm). Six knees were tested under these standard conditions for 4 million cycles. Six knees were tested under these conditions with the addition of lateral femoral condylar lift off, for 5 million cycles. The lubricant used was 25% newborn calf serum. Wear of the inserts was determined gravimetrically. Under the standard kinematic conditions the mean wear rate with 95% confidence limits was 8.8 ± 4.8 mm 3/million cycles. When femoral condylar lift off was simulated the mean wear rate increased to 16.4 ± 2.9mm 3/million cycles, which was statistically significantly higher (p <
0.01, Students t-test). The wear patterns on the femoral articulating surface of all the inserts showed more burnishing wear on the medial condyle than the lateral. However, in the simulation of lift off the medial condyle was more aggressively worn with evidence of adhesion and surface defects. The presence of lateral femoral condylar lift off accelerated the wear of PFC Sigma cruciate retaining fixed bearing knees. The lateral lift off produced uneven loading of the bearing, resulting in elevated contact stresses and hence more wear damage to the medial side of the insert. The implications of condylar lift off include increased wear of the polyethylene and possible osteolysis.
The outcome of complex acetabular reconstruction was evaluated in twenty-one patients who were confined to a wheelchair or bed because of pain from acetabular metastases. Reconstruction rings were used where bone loss exceeded 50% of the acetabulum. Six roof reinforcement-rings, eight ilioischial-rings and eight Harrington reconstructions were performed. All but two patients(90%) became ambulatory without pain. Median survival was nine months. Two patients underwent acetabular revision for recurrence. These results support the role of acetabular reconstruction for palliation of pain in appropriate patients with acetabular metastases. Metastatic disease of the acetabulum is painful and disabling. Operative intervention is indicated in certain patients with pathologic fractures, and non-responders to adjuvant treatment. The functional outcome of hip arthroplasty with reconstruction rings was evaluated in twenty-one patients with acetabular metastases between 1989 and 2001. Preoperatively all patients were confined to a wheelchair or bed and used significant narcotic medications. Preoperative radiotherapy was employed in eighteen cases (90%) and 30% had undergone chemotherapy. AAOS classification of the acetabular lesion revealed: six-type II, seven-type III and eight-type IV deficiencies. All cases required a reconstruction ring due to bone loss exceeding 50% of the acetabular dome. Six roof reinforcement rings, eight ilioischial rings and eight Harrington reconstructions with rings were performed in this group. Determination of the reconstructive technique was based on preoperative computerized tomography and intraoperative examination of the acetabular deficiency. All but two patients (90%) became ambulatory without significant pain. Eleven patients used a walker or two canes and nine walked with one or no canes. Median survival was nine months and patients with visceral involvement had a shorter duration. Eight early post-operative complications developed in six patients (29%). In two patients the acetabular construct failed with cup migration due to locally recurrent disease; both were successfully revised. The results of complex acetabular reconstruction for metastatic disease validate its role for palliation of pain and to improve ambulatory status. Preoperative planning with computerized tomography can assist in classifying acetabular bone loss and determining optimal reconstruction technique.
Many authors believe that size, histological grade and depth are the best predictors of outcome in soft tissue sarcoma. Enneking’s surgical staging system included compartmental status, and was intended to guide surgical intervention as well as provide prognostic information. Advances in surgical and radiotherapy techniques may mean that extracompartmental status is no longer a poor prognostic factor. We compared a group of popliteal fossa sarcomas with a group from the posterior thigh, and found that although the former group required more extensive surgery to obtain wide margins, their functional and survival outcomes were similar. No single staging system has been generally accepted for extremity soft tissue sarcoma, although histologic grade, size and depth are widely accepted as prognostic indicators. Enneking outlined a surgical staging system which used compartmental status as a predictor of outcome. However, surgical reconstruction and adjuvant radiotherapy have advanced considerably. We wanted to know if a tumour arising in the popliteal fossa still had poorer survival or functional outcome in the light of these advances. We identified twenty-three patients who had sarcomas of the popliteal fossa and forty-six patients who had sarcomas of the nearby posterior thigh compartment. Popliteal sarcomas were not of a different size or more likely to present with metastasis. Popliteal tumours more frequently required reconstructive techniques such as local or free tissue transfer and skin grafting than posterior thigh tumours (39.1% v 4.3% respectively). Popliteal tumours were also more likely to undergo a dissection or reconstruction of the major neurovascular structures of the lower limb (30.4% v 0% respectively). There was no difference in local or systemic recurrence rates between the groups. TESS and MSTS 1987 functional scores also showed no difference between the groups. We conclude that popliteal fossa sarcomas require a greater level of surgical intervention to follow sound principles of sarcoma resection and achieve reconstruction of the ensuing soft tissue defect. However, if these principles are followed in a planned multidisciplinary setting, then survival and functional results similar to the posterior thigh can be expected.
A retrospective review of our prospectively collected database was undertaken and the functional and oncologic outcomes after Type One pelvic resections for bone tumours of the ilium and sacrum were analyzed. Seventeen patients were identified with a minimum followup after resection of twelve months. In seven patients the bone defect was reconstructed, with no reconstruction in the remaining ten patients. The functional/oncologic outcomes of the two groups are similar, however patients without reconstruction had fewer complications and less dependence on walking aids suggesting that reconstruction may not be justified. Management of defects created by Type One pelvic resections of large iliac bone tumours remains controversial. We reviewed the functional/oncologic outcome following resection with and without reconstruction. Similar functional/oncologic outcome was achieved in both groups suggesting that reconstruction is not justified. A retrospective review of our prospectively collected database was undertaken analyzing functional/oncological outcome of seventeen patients with Type One pelvic resection. Minimum follow up was twelve months (12–96). Outcome data was available on 8/10 patients managed without reconstruction (WOR), with residual ilium collapsing back onto sacrum, and on 5/7 patients with bone graft reconstruction (WR). Average age thirty-three years (WOR) and 48yrs (WR), (p=0.04), with average maximal tumour dimensions of 12cm and 9cm (p=0.1). The most frequent diagnosis was chondrosarcoma. The WOR group average TESS, MSTS 87 and MSTS 93 scores were respectively 73%, 18/35 and 58% at an average of 50 months (24–96) compared to 69%, 21/35 and 51% at an average of 37 months (12–60) for the WR group. 33% of WOR and 20% of WR patients did not require walking aids. Infection or wound necrosis occurred in 40% of WOR patients and 57% of WR patients. No local recurrences. The perceived advantages of no reconstruction are shorter operating times, reduced incidence of complications and improved functional outcome due to medialization of the weightbearing axis in the absence of hip abductors. The oncologic/functional outcomes of both groups were similar but in those not reconstructed there was a lower incidence of complications and walking aids.
A retrospective review of our prospectively collected database was undertaken to determine the functional and oncologic outcome following combined pelvic allograft and total hip arthroplasty (THA) reconstruction of large pelvic bone defects following tumour resection. There were twenty-four patients with a minimum followup of fifteen months. The complication rate following hemipel-vic allograft and THA reconstruction of resection Types I+II and I+II+III was high, but when successful this reconstruction resulted in reasonable functional outcome. In comparison, the functional outcome after allograft and THA reconstruction of isolated Type II acetabular resections was better and more predictable. Resection of large pelvic bone tumours often results in segmental defects with pelvic discontinuity and loss of the acetabulum. We reviewed the functional and oncologic outcomes following pelvic allograft and total hip arthroplasty (THA) reconstruction. Reconstruction of large pelvic defects including the acetabulum using hemipelvic allograft and THA is associated with high complication rates, however when successful provides reasonable function. In comparison, the outcomes of allograft and THA for acetabular defects alone are better and more predictable. A retrospective review of our prospectively collected database was undertaken. Minimum followup was fifteen months (15–167). Nineteen patients were hemipel-vic resections (twelve Type I+II and seven Type I+II+III, eleven cases including partial sacral resection) reconstructed by hemipelvic allograft and THA. Five patients had Type II acetabular resections, reconstructed with structural allograft, roof ring and THA. Osteosarcoma and chondrosarcoma were the most frequent tumours. All patients required walking aids. In the hemipelvic group there were two early deaths (peri-operative haemorrhage and aplastic anaemia). In seven patients (37%) the allograft remained intact without infection but three required revision THA for loosening. For these seven patients the functional outcome scores were TESS 64%, MSTS87 17/35 and MSTS93 of 45% (mean fifty-two months.). There were nine cases of deep infection (47%) with three patients maintaining a functional implant. The nineteenth patient was revised following allograft fracture. In the Type II acetabular group, three patients had no complications, and two patients dislocated. The average scores were TESS 78%, MSTS87 21/35 and MSTS93 64% (mean fifty-five months).
Two hundred and forty-one patients with extremity osteosarcoma presented to our institution between 1989 and August 2002, thirty-six of whom had a pathologic fracture. There were twenty-five limb salvage surgeries and ten primary amputations, with three limb salvage surgeries requiring secondary amputations. One patient had an unresectable tumor and was treated palliatively. At mean follow-up of 96.9 months there was one local recurrence and eighteen patients were alive without disease in the pathologic fracture group. There was no survival difference between the pathologic fracture group with no metastases at presentation and the non-pathologic fracture group with no metastases (119.4 months vs 134.3 months, log rank 0.83, p=0.36). To examine the outcome of osteosarcoma patients that present with a pathologic fracture as compared to those patients without a pathologic fracture. There was no significant difference in the rate of amputation vs limb salvage surgery in osteosarcoma patients that presented with a pathologic fracture as compared to those without. There was no difference in the two groups’ disease-free and overall survival, for those patients that presented without metastatic disease. Presentation with a pathologic fracture in osteosarcoma does not preclude limb salvage surgery and is not a prognostic indicator for decreased survival. Retrospective review of all patients presenting to our institution with extremity osteosarcoma between 1989 and August 2002. There were two hundred and forty-one patients with extremity osteosarcoma, thirty-six of whom presented with a pathologic fracture. In the pathologic fracture group, there were nineteen males and seventeen females. Twenty-five were treated with limb salvage surgery, ten required a primary amputation and one was unre-sectable. Three limb salvage surgery patients required a secondary amputation. Sevenpatients presented with metastatic disease. Twenty-eight of the thirty-six patients received (neo) adjuvant chemotherapy. At last follow-up, eighteen patients were alive no evidence of disease (51.4%), three were alive with disease, eleven were dead of disease and three were deceased from other causes. There was one local recurrence (2.8%). Mean overall survival was 119.4 months (0–147.1) for patients with a pathologic fracture and no metastasis at presentation and 134.3 months (0–172.5) for patients with no pathologic fracture and no metastasis (log rank 0.83, p=0.36).
This study was undertaken to assess the contribution of pulmonary fat embolism caused by intramedullary femoral canal pressurization to the development of acute lung injury in the presence of resuscitated hemorrhagic shock. Twenty-seven NZW rabbits were randomly assigned into one of four groups: resuscitated hemorrhagic shock and fat embolism, resuscitated hemorrhagic shock, fat embolism, and control. Fat embolism was induced via intramedullary cavity with a 1–1.5 ml bone cement injection. Only the animals that underwent resuscitated shock and fat embolism displayed amplified neutrophil activation and alveolar infiltration. These findings suggest that the combination of resuscitated shock with fat embolism initiates an inflammatory response, which may play a role in the development of fat embolism syndrome. The objective of this study was to assess the contribution of pulmonary fat embolism caused by intramedullary femoral canal pressurization to the development of acute lung injury in the presence of resuscitated hemorrhagic shock. Only the animals that underwent resuscitated shock and fat embolism displayed amplified neutrophil activation and alveolar infiltration. These findings suggest that the combination of resuscitated shock with fat embolism initiates an inflammatory response, which may play a role in the development of fat embolism syndrome. CD11b mean channel florescence was only significantly elevated in the HR/FE group at two and four hours post knee manipulation. Moreover, greater infiltration of alveoli by leukocytes was only significantly higher in the HR/FE group as compared to controls. Twenty-seven NZW rabbits were randomly assigned into one of four groups: resuscitated hemorrhagic shock + fat embolism (HR/FE), resuscitated hemorrhagic shock (HR), fat embolism (FE), and control. Hypovolemic shock was induced via carotid bleeding for one-hour prior to resuscitation. For fat embolism induction, the intramedullary cavity was drilled, reamed and pressurized with a 1–1.5 ml bone cement injection. For evaluation of neutrophil activation, blood was stained with antibodies against CD45 and CD11b and analyzed with a flow cytometer. Animals were mechanically ventilated for four hours post surgical closure. Postmortem thoracotomy was performed, and three stratified random blocks of each lung were processed for histological examination. Our findings suggest that FE by itself does not cause lung injury, as there were no apparent differences between the control and FE animals. Only the HR/FE animals revealed a higher number of infiltrating neutrophils into alveolar spaces and greater neutrophil activation.
As patients live longer following treatment for soft tissue sarcomas, complications from treatment will continue to emerge. Predicting which patients are at risk allows for improved preoperative planning, treatment, and surveillance. The data presented here suggests that females greater than fifty-five years of age treated with high dose, postoperative radiotherapy in combination with limb salvage surgery for soft tissue sarcomas are at an increased risk of post irradiation fractures. Unlike previous reports, a significantly higher rate of fracture occurred in patients who received higher doses (60 or 66Gy) of radiation versus lower doses (50 Gy). This retrospective study was performed to determine if the timing and dosage of radiotherapy are related to the risk of post radiation pathologic fracture following combined therapy for lower extremity soft tissue sarcomas. Three hundred sixty-four patients with sarcomas treated with external beam radiation therapy and limb salvage surgery were evaluated. High dose radiation was defined as 60 Gy or 66 Gy; low dose as 50Gy. Radiation timing schedules were preoperative, postoperative, or preoperative with a postoperative boost. Univariate and multivariate analysis was used to determine which factors were associated with fracture risk. Twenty- seven pathologic fractures occurred in twenty-three patients. Twenty- four fractures occurred in twenty patients who were treated with high dose radiation. Sixteen of these patients had postoperative radiation (fourteen patients received 66Gy, two received 60Gy), and four had pre-operative radiation with a postoperative boost (total dose = 66Gy). Three fractures occurred in three patients who received low dose preoperative radiation (50Gy). Both high dose radiation (versus low dose) (p=.001) and preoperative radiation (versus postoperative) (p =0.002) were associated with a risk of fracture. Findings in this study were consistent with previous reports in that females over fifty-five years of age who undergo removal of a thigh sarcoma combined with radiation therapy are at a higher risk of a pathologic fracture, and differs in that there was a significantly higher rate of fracture in patients who received higher doses (60 or 66Gy) of radiation versus lower doses (50 Gy), and when radiation therapy was given postoperatively versus preoperatively.
Forty-six patients with an uncemented proximal tibial endoprosthesis were reviewed following resection of a proximal tibial tumor. The mean age was thirty-four years and the majority were male. The most common malignant diagnosis was osteosarcoma. Oncologic and functional analysis was performed on these cases. At latest follow-up thirty of the patients remain alive with no evidence of disease and eleven had died. The most common complication was deep infection (7/46). Only six patients had mechanical prosthesis related complications. At latest follow up the average TESS score was 76.3 and MSTS score 75.5 with an average extensor lag of 6.5o. To review the oncologic and functional results of a series of forty-six uncemented proximal tibia tumour replacements. A retrospective review of our prospectively collected database revealed forty-six patients with an uncemented proximal tibial replacement following tumour excision. The data was analysed with respect to patient demographics, operative and prosthetic complications. Oncologic diagnosis and results and functional results were also reviewed. The average age of the forty-six patients was thirty-four years (14–73) with thirty-three males and thirteen females. The most common diagnosis was osteosarcoma. There were four cases of benign GCT. At an average follow-up of 85.8 months (11–170), thirty were alive with no evidence of disease while eleven patients had died of their disease. Four patients were alive with evidence of disease at latest follow-up and one patient had died of unrelated causes. The most common operative complication was infection (9/46) with seven of these being deep infections requiring prosthesis removal, followed by mechanical problems including stem fracture (3/46) and bushing failure (3/46) also requiring operative intervention. Functional assessment revealed an average extensor lag of 6.5o with an average ROM of 83.6o, average TESS scores of 76.3 and MSTS 93 scores of 75.5. Large series of uncemented proximal tibial endoprostheses are uncommon in the literature. In our series there is a low rate of aseptic loosening at an average seven year follow-up, but this is offset by problems including infection and prosthetic fracture. Overall the functional and oncologic results remain satisfactory.
To review the results of limb lengthening and deformity correction in fibular hemimelia, fifty-five patients with fibular hemimelia underwent limb reconstruction at Sheffield Children’s Hospital. According to Achter-man and Kalamchi classification, twenty-six were classified as Type IA, six as Type IB and twenty-three as Type II fibular hemimelia. All patients had at least some shortening of ipsilateral femur but forty-nine had sig-nificant femoral deficiency. Lengthening of tibia and in significant cases femur was done using De Bastiani or Vilarrubias or Ilizarov methods. Ankle valgus and heel valgus were corrected through osteotomies either in the supramalleolar region or heel. Equinus was corrected by lengthening of tendoachelis with posterior soft tissue release and in severe cases using Ilizarov technique. The average length gained was 4.2 cm (range 1 to 8) and the mean percentage of length increase was 15.82 (range 4.2 to 32.4). Mean bone healing index was 54.23 days/cm. Significant complications included knee subluxation, transient common paroneal nerve palsy, and recurrence of equinus and valgus deformity of foot. Overall alignment and ambulation improved in all patients. Knee stiffness due to cruciate deficient subluxations needed prolonged rehabilitation. Presence of 3-ray foot gives a better functional result and cosmetic acceptance by patients. The Ilizarov frame has the advantage to cross joints and lengthen at the metaphysis. Limb reconstruction in fibular hemimelia using limb lengthening and deformity correction techniques improve functional status of involved lower limb.
In this paper, a retrospective review was undertaken of a large musculoskeletal tumour database to identify patients who presented with tumours of the foot and ankle. Soft tissue tumours occurred more frequently than bone tumours, and were also more frequently malignant than bone tumours. In contrast to the more recent trend towards limb-preserving surgery in other anatomic areas, malignant tumours of the foot and ankle were frequently unresectable and were treated with amputation. Although the majority of extremity tumours that present to the orthopaedic surgeon are found in the proximal limbs or around the knee, tumours of the ankle and foot are also relatively common. The purpose of this study is to identify the frequency with which benign and malignant bone and soft tissue tumours occur in the foot and ankle and the oncologic and surgical outcomes of these patients. A retrospective review of a large musculoskeletal tumor database in a tertiary referral center from the years 1986–2002 was undertaken. For oncologic outcomes, a minimum two-year follow up was considered. A total of one hundred and sixteen bone and one hundred and seventy-one soft tissue tumours were identified. Seventy-seven bone tumours were benign and thirty-nine were malignant. Sixty-six soft tissue tumours were benign and one hundred and five were malignant. The most common benign bone tumour was giant cell tumour and osteosarcoma was the most common malignancy. Malignant fibrous histiocytoma was common in the distal leg but synovial sarcoma and clear cell sarcoma were more common in the foot. Twenty patients with bone malignancies (51%) and twenty-four with soft tissue sarcomas (23%) had amputation as definitive surgical management. Death from metastases occurred in 25% of patients with bone malignancies and 10% of soft tissue sarcomas. At this center, the majority of bone tumours treated are benign but the majority of soft tissue tumours are malignant. Limb salvage is often not possible and amputation for local tumour control is necessary far more often than in other anatomic sites.
Lymph node metastasis in soft tissue sarcoma is considered to be a rare event (1.6–8.2%), From 1986 to 2001 1066 patients with extremity soft tissue sarcoma were treated surgically (+/− adjuvant therapy) at our institution. Thirty-nine patients (3.6%) were identified with lymph node metastasis, most common histological subtypes were: Epitheliod sarcoma (3/15), rhabdomyosarcoma (4/21), clear cell sarcoma (2/18), and angiosarcoma (2/18). Comparing expected five- year survivorship, we found that surprisingly in this study, extremity soft tissue sarcoma patients initially presenting with lymph node metastases had survival comparable to patients with high grade soft tissue sarcoma and no metastases. To determine the outcome in patients with soft tissue sarcoma (STS) of the limbs that presented with lymph node metastasis (LNM) at diagnosis or developed them after it, comparing to all STS of limbs population that was treated at our center. LNM in soft tissue sarcoma is considered to be a rare event (1.6–8.2%) with a devastating effect on the outcome,our study represent one of the largest reported cohorts, and suggest that agressive approach to LNM might contribute to survivorship. Thirty-nine patients (3.6%) were identified with LNM along their course of disease Thirteen patients presented with both lymphatic and systemic disease while twenty-six had isolated LNM at time of diagnosis. The mean follow-up from diagnosis of the primary tumor was 46.3 months (range zero to one hundred and forty-eight), and from diagnosis of lymph node involvement was 29.9 months (range zero to one hundred and twenty). Expected five year survival in patients initially presenting with LNM was comparable to patients with high grade soft tissue sarcoma and no metastases. From Jan’ 1986 to Dec’ 2001 1066 patients with extremity STS were treated at our institution. Fifteen patients presented with LNM at time of first diagnosis, and twenty-four subsequently developed LNM after it. Linear regression analysis and Kaplan-meier curves were used to compare expected survivorship in all patients with STS of limbs. Comparing expected five- year survivorship, we found that Surprisingly in this study, extremity STS patients initially presenting with LNM had survival comparable to patients with high grade soft tissue sarcoma and no metastases.
