Aim: To determine the ultra-structural morphology of bone in CLLLD.

Materials and Methods: Bone biopsies were taken from 8 patients with CLLLD undergoing surgery for limb reconstruction procedures. Specimens were fixed and processed for Electron microscopy using standard processing protocol. Ultra-thin araldite sections were stained with uranyl acetate and lead citrate and viewed in Philips CM12 electron microscope. Muscle biopsies were also undertaken.

Results: There were 5 boys and 3 girls of a mean age of 8.8 years (range 3 to 14 years). 6 had predominantly femoral deficiencies and 2 had combined femoral and fibular deficiencies. All specimens showed abnormal collagen fibril morphology. They showed variable diameter with irregular outlines in transversely section bundles and appeared unravelled in longitudinally sectioned bundles. The osteoid was disorganised in 4 of the 8 specimens and osteoblasts showed necrotic changes in 5 out of 8 specimens. Patchy mineralisation and increased proteoglycan distribution was observed in 3 out of 8 specimens.

Conclusion: Bone in CLLLD shows ultra-structural changes in collagen and osteoblasts that may account for the retarded bone growth and poor regenerate formation that occurs during limb lengthening in these patients.

Upper limbs are commonly involved in Arthrogyposis Multiplex Congenita. They may be involved in isolation or in combination with lower limbs. There are two patterns of involvement in upper limbs. The most common (type I) pattern presents with adduction and internal rotation at the shoulder, extension at the elbow, pro-nation of the forearm and flexion deformity of the wrist, indicating involvement of the C5 and C6 segments. These deformities can be quite disabling and may require surgery to help improve function. We present our long-term results with pectoralis major transfer procedure (as modified by senior author MJB) to restore elbow flexion in seven patients (ten procedures).

Results: Early results in all our patients were quite encouraging. Six patients retained useful power in transferred pectoralis major muscle and maintained the arc of flexion, which was attained following tricepsplasty. However, as children were followed up a gradually increasing flexion deformity and decreasing flexion arc were observed in eight elbows. The onset and progression of flexion deformity was gradual and progressive. The flexion deformity reached ninety degrees or more in all cases.

Conclusions: Results of pectoralis major transfer to treat extension contracture of the elbow in arthrogryposis deteriorate with time due to development of recalcitrant flexion deformity of the elbow. Presently we recommend this procedure on one side only in cases of bilateral involvement because if one procedure is carried out it would be possible for this hand to get to the mouth for feeding and the other unoperated side would be able to look after the perineal hygiene

Children with osteogenesis imperfecta(OI) have multiple long bone fractures with subsequent deformities. The mainstay of treatment is correction with multiple osteotomies and intramedullary fixation. The Shefffield intramedullary telescoping rod system has been successful in the treament of long bone fractures and deformities (Wilkinson et al ,JBJS-B,1998) Bisphosphonates (Pamidronate -1- 1.5mg/kg/day)have been used as adjuvant therapy in the treatment of OI since the last five years. The perceived benefits include reduction in fracture frequency, improvement in bone density and a general feeling of well being.

We present our experience of five cases of OI who developed infections around thier Sheffield telescoping rods while on Pamidronate therapy. There was only one case of sepsis over a ten year period(over eighty patients)in a previously reported series from our centre.

The time interval between the start of Pamidronate therapy and the diagnosis of infection varied between 12–36 months ie. between 4–12 cycles of Pamidronate (parenteral administration over a three day period at three month intervals). All patients had their intramedullary rods in situ from anywhere between 2–7 years. The infections were low grade with a 2–3 month period of dull ache prior to actual presentation. Intrestigly though all patients had multiple rods in situ, only one of their femoral rods was affected and they did not have any other infective focus at the time of diagnosis. Three patients presented with thigh abcesses while the other two presented with ipsilateral knee pain and effusion. All had raised inflammatory markers, radiological signs of sepsis with Staph Aureus the commonest infecting organism.

Those cases presenting with abcesses were treated by drainage and rod removal, however only antibiotics were sufficient in the rest. The relationship between Pamidronate therapy and these infections is not absolutely clear and has not been reported previously. The possible links are discussed and a high degree of suspicion is recommended for those cases of OI on bisphosphonate

Objective: To review the hip subluxations or dislocations occurring during femoral lengthening in patients with congenital longitudinal lower limb deficiencies.

Methods: Sixty-three patients with congenital longitudinal lower limb deficiencies underwent femoral lengthening using either De Bastiani, Villarubias or Ilizarov technique. Acetabular index, medial joint space, CE angle of Wiberg, acetabular angle of Sharp and neck-shaft angle were measured on anteroposterior radiographs of hip before, during and after lengthening. The Acetabulum was considered dysplastic when the Sharp angle was more than 45 degrees. Hip was considered to be subluxed when the medial joint space increased during lengthening.

Results: During femoral lengthening, eleven hips sub-luxed as measured by the increase in medial joint space and one hip dislocated. All these hips had a preoperative acetabular index more than 25 degrees, CE angle less than 20 degrees and Sharp angle more than 45 degrees. The average neck-shaft angle was 75 degrees. Following subluxation, lengthening was stopped and the hips were reduced in hip spica after adductor and sartorius tenotomies. In one patient femoral shortening and acetabulo-plasty had to be done to reduce the subluxation. No case of avascular necrosis was noted.

Conclusion: Hip subluxation during femoral lengthening of congenital longitudinal lower limb deficiencies tends to occur when the acetabular index is more than 25 degrees, Sharp angle is more than 45 degrees, CE angle is less than 20 degrees and when there is associated femoral coxa vara. Careful preoperative assessment is required, and if need be hip reconstruction prior to lengthening. Close monitoring during lengthening is recommended.

Study background: The management of patients presenting in primary care with a “new episode of back pain” using the RCGP guidelines by a nurse practitioner (NP) compared to a control group given ‘usual care’ by the GP.

Methods and Results: The evaluation includes sequential monitoring of LBOS, audit of documentation for both groups of patients to assess application of guidelines and patient recall of key information.

Conclusion: The NHS Plan (2000) called for national standards for treating all major conditions in “Shifting the Balance of Power- the next steps” (2001) a clear criterion is that “service outcomes which provide better and better validated information” will form part of the performance rating. These two documents highlight the need for more user and client involvement in service development but this needs to be carefully monitored and linked to effective evidence.

This study demonstrates that the NP documentation follows the guidelines identified by the RCGP, conversely it was not possible to assess from the GP documentation if all the steps had been followed. The mean average LBOS in the NP patients was slightly higher than those in the GP group, was this because these patients were having guideline applied care as opposed to “usual care”?

Evaluation of the patient recall of information shows the NP sent five patients for X-ray even though this did not occur and is not recommended in guidelines. Conversely twenty-three patients can remember being given the “Back Book” by the GP but this was only documented in three cases.

We believe that patient recall demonstrates an ineffective way to measure outcome and funding allocation for back pain management and needs to more accurately reflect the evidence.

Increased incidence of complications has been reported when lengthening limbs with underlying bone disorders such as dysplasias and metabolic bone diseases. There is a paucity of literature on limb lengthening in Osteogenesis Imperfecta (OI), probably due to the concern that the bone containing abnormal collagen may not tolerate the external fixators for a long term and there may not be adequate regenerate formation from this abnormal bone.

We performed limb lengthening and deformity correction of nine lower limb long bones in six children with OI. Four children were type I and two were type IV OI as per Sillence classification. The mean age was 14.7 years. All six children had lengthening for femoral shortening and three of them also had lengthening for tibial shortening on the same side. Angular deformities were corrected during lengthening. Five limb segments were treated using a monolateral external fixator and four limb segments were treated using an Ilizarov external fixator. In three children, previously inserted femoral intramedullary nails were left in situ during the course of femoral lengthening. The average lengthening achieved was 6.26 cm. Limb length discrepancies were corrected to within 1.5 cm of the length of the contralateral limb in five children. In one child with fixed pelvic obliquity and spinal scoliosis, functional leg length was achieved. The mean healing index was 33.25 days/cm of lengthening. Among the complications significant ones included, one deep infection, one fracture through the midshaft of the femur, and development of anterior angulation deformity after the removal of the fixator in one tibia. Abnormal bone of OI tolerated the external fixator throughout the period of lengthening without any incidence of migration of wires and screws through the soft bone when distraction forces were applied. The regenerate bone formed within the time that is normally expected in limb lengthening procedures performed for other conditions. We conclude that despite abnormal bone characteristics, limb reconstruction to correct limb length discrepancy and angular deformity can be done safely in children with OI.

113 consecutive patients with soft tissue sarcoma treated by excision and reconstructive flaps were studied to assess the risk of complications and to compare local tumour control with those in whom primary wound closure was possible.

Minimum follow-up was 24 months and mean age was 55 years (16–95). The sarcoma was located in the lower extremity in 83 and upper extremity 30 patients. Significant wound complications developed in 37 patients (33%). The most common complications were wound infections or partial necrosis occurring in 16% (18/113) and 13% (15/113) respectively. Complete flap necrosis requiring flap removal occurred in 6 patients (5%). Three patients (2.3%) required amputation as a result of complications. Significant risk factors for development of wound complications include location of tumour in the lower limb compared to upper limb (relative risk 2.3, p=0.02) and use of pre-operative radiotherapy compared to no or post-operative radiotherapy (relative risk 2.05, p=0.02). There was no difference in rates of complications in patients with free or pedicled flaps, tumours < or > 5cm, distal or proximal location of tumour.

The rates of negative excision margins (80%) and wound complications in patients who required reconstructive flaps were not different from that for the other patients treated at our centre who did not require reconstructive flaps.

The use of soft tissue reconstructive flaps did not reduce the risk of positive excision margins or the rates of wound complications. The risk of amputation secondary to flap complication or failure is low.

Acute lateral dislocation of the patella has been associated with disruption of the medial restraints of the patella. Following non-operative management there is a redislocation rate of up to 44%. This is an observational study testing whether sonography is a reliable method of assessing the medial retinaculum after acute dislocation of the patella.

Ten patients following acute patellar dislocation had an ultrasound scan (USS) performed by an experienced musculoskeletal radiologist. Each patient subsequently had an examination under anaesthetic, arthroscopy, and repair of the ruptured structures. The ultrasound reports were compared to the surgical findings to determine the accuracy of this investigation.

USS located deficiencies in the ligamentous attachments to the medial border of the patella and the presence of avulsed bony fragments, all of which were confirmed at operation. The sonographic diagnosis of haematoma or torn fibres in the vastus medialis obliquus corresponded with our operative findings.

The most significant findings were the correlation of free fluid around the medial collateral ligament (MCL) with avulsion of the femoral attachment of the medial patellofemoral ligament (MPFL) and the presence of avulsed fragments of bone from the medial border of the patella.

Sonography, in cadaveric studies consistently identifies the retinacula and like MRI offers a distinctive constellation of findings that can be used in diagnosis and therefore play a significant role in directing surgical management of these patients. We have found Sonography to be readily available and accurate.

This report does not include surgical outcome since the follow up is short and incomplete. We do, however, feel that ultrasound shows the state of the soft tissue restraints of the patella following lateral dislocation.

812 consecutive patients with soft tissue sarcoma of the extremity were studied to compare the characteristics and outcome of patients who had primary amputations and limb preserving surgery.

Patients with primary amputations were more likely to have metastases at presentation, high-grade tumours, larger tumours and were older.

The most frequent indications for primary amputation were tumour excision which would result in inadequate function and large extracompartmental tumours with composite tissue involvement including major vessels, nerves and bone.

The requirement for primary amputation was a poor prognostic factor independent of tumour grade, tumour size and patients’ age.

To determine if rates of local recurrence and metastasis differ in upper versus lower extremity sarcomas.

Prospectively collected data relating to patients undergoing limb-sparing surgery for extremity soft tissue sarcoma between January 1986 and April 1997 were analysed. Local recurrence-free and metastasis-free rates were calculated using the method of Kaplan and Meier. Univariate and multivariate analyses of potential predictive factors were evaluated with the log-rank test and the Cox proportional hazards model.

Of 480 eligible patients, 48 (10. 0%) had a local recurrence and 131 (27. 3%) developed metastases. Median follow-up of survivors was 4. 8 years (0. 1 to 12. 9). There were 139 upper and 341 lower extremity tumours. Upper extremity tumours were more often treated by unplanned excision before referral (89 vs 160, p< 0. 001) and were smaller (6. 0cm vs 9. 3cm, p< 0. 000). Lower extremity tumours were more often deep to or involving the investing fascia (280 vs. 97, p< 0. 003). The distribution of histological types differed in each extremity. Fewer upper extremity tumours were treated with adjuvant radiotherapy (98 vs. 289, p< 0. 000).

The 5-year local recurrence-free rate was 82% in the upper and 93% in the lower extremity (p< 0. 002). Local recurrence was predicted by surgical margin status (hazard ratio 3. 16, p< 0. 000) but not extremity (p=0. 127) or unplanned excision before referral (p=0. 868).

The 5-year metastasis-free rate was 82% in the upper and 69% in the lower extremity (p< 0. 013). Metastasis was predicted by high histological grade (hazard ratio 17. 28, p< 0. 000), tumour size in cm (hazard ratio 1. 05, p< 0. 001) and deep location (hazard ratio 1. 93, p< 0. 028) but not by extremity (p=0. 211).

Local recurrence is more frequent after treatment for upper compared with lower extremity sarcomas. Variation in the use of radiotherapy and differences in histological type may be contributory. Metastasis is more frequent after treatment for lower extremity sarcomas because tumours tend to be large and deep.

Aim: To determine the effectiveness of arthroscopic surgery, without excision of the radial head, in elbows with end stage arthritis of the radiocapitellar joint.

Methods: Twenty-three elbows with bone-on-bone degeneration of the radio-capitellar joint, but with only minor degeneration of the humeroulnar joint, had arthroscopic surgery, with synovectomy, removal of loose bodies and excision of impinging tissues and bone. The average age was 51 years (range: 16 years to 59 years). Evaluation was by a questionnaire and the follow-up was after a minimum of one year.

Results: The average follow up was 41 months (range 12 months to 83 months). Twenty-one of 22 patients reported improvements. Six patients were pain free, 12 had mild residual pain and six had significant, continuing pain. Only three patients reported residual lateral elbow pain. The average visual analogue pain score was 3.4. According to the Mayo elbow function score, there were eight excellent, seven good, six fair, and three poor outcomes.

Conclusions: Satisfactory improvements in symptoms and function were obtained in arthritic elbows with arthroscopic surgery, even in the presence of severe radiocapitellar arthritis.

Aim: To evaluate the results of arthroscopic resection of the superomedial corner of the scapula, using a new superior portal, in patients with painful snapping scapulæ.

Methods: An analysis was made of 10 patients who had each undergone arthroscopic resection of the superomedial corner of the scapula. The patients were evaluated by questionnaire and clinical examination, and the results assessed by the UCLA rating score.

Results: There were four women and six men with a mean age 26.9 years (range: 16 to 40 years). The average duration of symptoms was 53.2 months (range: 12 to 154 months). Their x-rays and CT scans were normal. The average follow-up period was 11.3 months (range: three to 23 months). There were no post-operative complications. The scapulothoracic crepitus disappeared in two patients, decreased in seven patients, and remained the same in one patient. The mean postoperative visual analog pain scale was 2.7. All felt the procedure to be worthwhile. On the UCLA score there were four excellent, four good and two fair results.

Conclusions: Scapulothoracic arthroscopy using medial and superior portals is a safe procedure. Resection of the superomedial corner of the scapula reliably improved symptoms from the painful snapping scapula.

Aim: To determine the long-term outcome of surgery for rotator cuff disorders.

Methods: Ninety-two patients were followed up, after a minimum of nine years following rotator cuff surgery, including arthroscopic and open subacromial decompression, and repair of a rotator cuff tear. The results were assessed with the UCLA rating score. These results were compared with another group with a two-year follow-up.

Results: The follow-up periods for the 92 patients were from nine to 14 years. There were 58% of patients in the good or excellent group, 23% in the fair, and 19% in the poor. The results in cases with rotator cuff repairs were similar to those with only subacromial decompressions. The long-term results were a little worse than the results in the two-year follow-up group.

Conclusions: In some cases there was a gradual deterioration over time in shoulder symptoms following rotator cuff surgery. After 10 years, 19% had a poor result.

Localised Langerhans-cell histiocytosis of bone (eosinophilic granuloma) is a benign tumour-like condition with a variable clinical course. Different forms of treatment have been reported to give satisfactory results. However, previous series all contain patients with a wide age range. Our aim was to investigate the effect of skeletal maturity on the rate of recurrence of isolated eosinophilic granuloma of bone excluding those arising in the spine.

We followed up 32 patients with an isolated eosinophilic granuloma for a mean of five years; 17 were skeletally immature. No recurrences were noted in the skeletally immature group even after biopsy alone. By contrast, four of 13 skeletally mature patients had a recurrence and required further surgery. This suggests that eosinophilic granuloma has a low rate of recurrence in skeletally immature patients.

The aim of this study was to compare implementation of RCGP guidelines in patients in Primary Care with acute low back pain between GP and Nurse Practitioner. This report presents preliminary results.

The intention was to recruit 200 patients presenting to GP with new episode of back pain. 50% randomised to NP care, 50% to GP care. Outcome measured by documentation audit and patient feedback. Individuals complete a questionnaire which includes a Low Back Outcome Score (LBOS) at 14 weeks, 6,12 and 24 months. All patients in NP arm given back book and advised against bed rest.

Initial Findings: (n = 145): The LBOS score was identical (30) for the 73 patients randomised to nurse practitioner care and the 72 with routine GP care. There were no significant differences between the scores at 14 weeks and 6 months, with an increase in LBOS to 45–49, but numbers dropping to 28 in the NP group and 26 in the GP group.

Process audit at 14 weeks: Only 10 of NP patients were not given the back book compared with 74% for GP care. 13% of NP patients were prescribed bed rest against 18 for GP care.

Initial results suggest no significant difference in outcome between GP and Nurse Practitioner patients. Of interest is that 10% and 13% of patients failed to recall important features of management. This implies that audit of healthcare processes by patient questionnaire may be unsatisfactory.

We considered whether a positive margin occurring after resection of a soft-tissue sarcoma of a limb would affect the incidence of local recurrence. Patients with low-grade liposarcomas were expected to be a low-risk group as were those who had positive margins planned before surgery to preserve critical structures. Two groups, however, were expected to be at a higher risk, namely, patients who had undergone unplanned excision elsewhere with a positive margin on re-excision and those with unplanned positive margins occurring during primary resection.

Of 566 patients in a prospective database, 87 with positive margins after limb-sparing surgery and adjuvant radiotherapy were grouped according to the clinical scenario by an observer blinded to the outcome. The rate of local recurrence differed significantly between the two low- (4.2% and 3.6%) and the two high-risk groups (31.6% and 37.5%). This classification therefore provides useful information about the incidence of local recurrence after positive-margin resection.

We describe ten patients with Turner’s syndrome (karyotype 45, XO) who had leg lengthening for short stature. A high incidence of postoperative complications was encountered and many patients required intramedullary fixation as a salvage procedure. We discuss the reasons for this and highlight the differences between our findings and those of a similar series recently reported. In view of the considerable difficulties encountered, we do not recommend leg lengthening in Turner’s syndrome.

We describe a patient who developed avascular necrosis of both humeral trochleae after combination chemotherapy for acute lymphoblastic leukaemia. This presented as progressive stiffness of both elbows with little pain. Radiography and MRI confirmed the presence of avascular necrosis at both sites. This region corresponds to a watershed between the medial and lateral vascular arcades which supply the distal humerus and may explain the susceptibility of this bony region to avascular necrosis. Treatment involved capsulectomy of the elbow and removal of osteophytes giving a good functional outcome on both sides.

We used dual-energy x-ray absorptiometry (DEXA) to evaluate the extent of periprosthetic bone remodelling around a prosthesis for distal femoral reconstruction, the Kotz modular femoral tibial replacement (KMFTR; Howmedica, Rutherford, New Jersey). A total of 23 patients was entered into the study which had four parts: 1) 17 patients were scanned three times on both the implant and contralateral legs to determine whether the precision of DEXA measurements was adequate to estimate bone loss surrounding the anchorage piece of the KMFTR; 2) in 23 patients the bone mineral density (BMD) in different regions of interest surrounding the diaphyseal anchorage was compared with that of the contralateral femur at the same location to test whether there was consistent evidence of loss of BMD adjacent to the prosthetic stem; 3) in 12 patients sequential studies were performed about one year apart to compare bone loss; and 4) bone loss was compared in ten patients with implants fixed by three screws and in 13 without screws.

The mean coefficients of variation (SD/mean) for the 17 sets of repeated scans ranged from 2.9% to 7.8% at different regions of interest in the KMFTR leg and from 1.4% to 2.5% in the contralateral leg. BMD was decreased in the KMFTR leg relative to the contralateral limb and the percentage of BMD loss in general increased as the region of interest moved distally in the femur. Studies done after one year showed no consistent pattern of progressive bone loss between the two measurements. The ten patients with implants fixed by screws were found to have a mean loss of BMD of 42% in the most distal part of the femur, while the 13 without screw fixation had a mean loss of 11%.

DEXA was shown to have adequate precision to evaluate loss of BMD around the KMFTR. This was evident relative to the contralateral leg in all patients and generally increased in the most distal part of the femur. In general, it stabilised between two measurements taken one year apart and was greater surrounding implants fixed by cross-locking screws.

The Sheffield Expanding Intramedullary Rod System was developed after experiencing problems with existing rod systems in the management of osteogenesis imperfecta. Between 1986 and 1996 we treated 74 bones in the lower limb in 28 children at a median follow-up of 5.25 years. We have reviewed 24 children with a total of 60 rods.

Before surgery, all children had had multiple fractures of the lower limb. At review eight patients had experienced no further fractures, but three had suffered five or more subsequently.

Before initial stabilisation, 15 children had never walked, and only three (13%) used walking as their main means of mobility. After surgery, half of those who showed motor arrest were able to walk (p = 0.016). The number of patients able to walk, with or without aids, increased to 17 (p = 0.0001).

We have experienced no evidence of epiphyseal damage after the procedure, and complication rates requiring rod exchange have been low (7%).

We report three complete ruptures and one partial rupture of the flexor pollicis longus tendon in association with the insertion of a volar plate for the treatment of fracture of the distal radius. Rupture was associated with the chronic use of steroids.

We describe the functional results in 14 patients (7 men, 7 women) after subtotal scapulectomy for primary bone and soft-tissue tumours at a specialist musculoskeletal oncology unit. Eight had chondrosarcomas, two Ewing’s sarcomas, one aggressive fibromatosis and three soft-tissue sarcomas. The mean follow-up was 52 months (6 to 120). Analysis of residual symptoms and of range and strength of movement by physicians used the Musculoskeletal Tumour Society rating scale (MSTS). Physical disability was measured by the patients using the Toronto Extremity Salvage Score (TESS).

All 14 patients are still alive, two with systemic disease. Nine had more than 80% of their scapula resected but the glenohumeral joint was preserved in all cases. Eight had full movement and another two achieved 90° of flexion. The mean functional results were good to excellent in all except three patients (mean MSTS = 71.6 and TESS = 79.9). Two of these three patients had considerable pain as a result of brachial neuropathy.

Scapulectomy gives an excellent functional result if the glenohumeral joint is preserved. The rotator cuff could be removed without a severe functional deficit provided that the deltoid was reattached to the scapular remnant and the trapezius.

We studied the quantity and rate of formation of new bone during lengthening of 17 limb segments in 10 patients using dual-energy X-ray absorptiometry (DEXA), ultrasonography and radiography. Whereas new bone was detected by both DEXA and ultrasonography within 1 to 2 weeks of distraction, it was not visible on the radiographs until 4 to 8 weeks. Limb alignment and gap measurement were accurately assessed by DEXA without the need for standard radiographs or scanograms. With ultrasound the distraction gap appeared as an echolucent window which narrowed progressively producing a hyper-reflecting line after which further consolidation could not be assessed. As measured by DEXA the density of the new bone at this stage was approximately 45% of control values and did not represent normal cortication. Whereas ultrasound could be used to identify defects in mineralisation and to determine when to dynamise the fixator system, DEXA could measure the quantity and rate of formation of bone throughout lengthening.

We measured the extent and rate of new bone formation over an 18-month period before, during and after the lengthening of ten leg segments in six patients aged between 8 and 18 years, using dual-energy X-ray absorptiometry (DEXA). New bone formation could be identified within one week of the start of distraction. As lengthening proceeded, the bone density of the gap fell, reaching minimum values at the time of maximal distraction. Consolidation of the regenerating bone was started 1 to 2 weeks later in the tibia, and 2.5 to 3.0 weeks later in the femur. The rate of mineral accretion in new bone was significantly greater in the tibia than in the femur (16 +/- 1.86%/month, and 11 +/- 1.1%/month respectively; mean +/- SEM). There was significant osteoporosis distal to the osteotomy, more in the tibia than in the femur, particularly on the side of the fixator. The bone mineral density of the distal segment remained low at the time of fixator removal (44.2 +/- 5.58% and 61.0 +/- 4.2% of the control values at the tibia and femur respectively) and was only partially reversed by subsequent weight-bearing. We conclude that dual-energy X-ray absorptiometry provides an objective and quantitative assessment of new bone formation during leg lengthening. The technique also allows the measurement of the distraction gap and the assessment of leg alignment from the high-resolution images. Its use may decrease the requirements for conventional radiography.

We report the results of locked Seidel nailing for 30 fractures of the humerus. There were frequent technical difficulties at operation especially with the locking mechanisms. Protrusion of the nail above the greater tuberosity occurred in 12 cases, usually due to inadequate locking, and resulted in shoulder pain and poor function. Poor shoulder function was also seen in five patients with no nail protrusion, presumably because of local rotator cuff damage during insertion. Our results suggest that considerable modifications are required to the nail, and possibly to its site of insertion, before its use can be advocated.

We discuss the role of primary knee arthroplasty in supracondylar and intercondylar fractures of the femur in elderly patients with reference to 13 cases. This method of treatment is shown to be effective and to have good results. It is recommended for all type C and some type A supracondylar fractures in old people.

Five patients with Boyd type II congenital pseudarthrosis of the tibia underwent excision of the pseudarthrosis and double onlay bone grafting. Stability was maintained by extending intramedullary rods. Clinical union was achieved in all cases at a mean of 8.6 months (range six to 11). The rods extended by 15.7% (range 2% to 31.4%) as growth occurred. One rod was removed because of infection and a vascularised free fibular graft was subsequently performed. The extending rods provided stability while union occurred and did not require revision as the legs grew. The rods can be removed easily and have not jeopardized further surgical options.

We made a prospective study of 111 children with acute hip pain to assess whether ultrasound can replace traditional radiography. An effusion was diagnosed in 71% by ultrasound but in only 15% by radiography. This effusion persisted for a mean of nine days; symptoms lasted for five days. Two patients found to have Perthes' disease had longer-lasting effusion and symptoms. Patients without an effusion had no obvious cause for their pain, so the pressure of an effusion from a transient synovitis does not account for all patients with irritable hips. Patients with an effusion persisting for over 24 days (the mean + 2 s.d. of our series) had more symptoms, a significantly larger effusion and greater limitation of movement. They may be more at risk for avascular necrosis. We found that radiographic examination influenced the immediate management of only two patients, those with Perthes' disease. We therefore propose a protocol of management for irritable hip, using ultrasonography at the first presentation of certain categories of patients. This would reduce the number of early radiographs by 75%.

We report the results of using 83 expanding intramedullary rods in 24 children with osteogenesis imperfecta after a mean follow-up of five years three months. In all, 62% of the rods have expanded after one primary operation. Thirty-four additional operations were necessary; 11 for the correction of rotation or angulation deformities and 23 for revision of the rod or T-piece. All these revisions were successful. Complications were more frequent in children who required very small rods. Problems with Bailey-Dubow rods led to the development of the Sheffield rod system; 17 bones treated with these rods are included in the series. Before surgery only eight of the 24 children were able to walk but at review 20 children were walking, 15 without walking aids. Elongating intramedullary rods should be available to all children with osteogenesis imperfecta as they improve walking capability, reduce the number of fractures, prevent deformity and allow integration of the child into society.

We report nine cases of irreducible congenital dislocation of the knee which were treated by early operation with good results. All were resistant to conservative measures and operation was performed at an average age of nine months. The essential abnormality was a short quadriceps muscle together with subluxation of the hamstring muscles to lie anterior to the axis of knee flexion. The quadriceps tendon was lengthened by VY-plasty and in six cases additional length was gained by proximal mobilisation of the muscle. After operation all the patients were able to walk.

After having had a standard decompression for anterior compartment syndrome, five patients presented with persistent symptoms and pressure values above normal. A repeat procedure combined with fasciectomy relieved their pain; postoperative pressure values were normal.

We present three cases of a previously undescribed condition characterised by unilateral tibia vara associated with an area of focal fibrocartilaginous dysplasia in the medial aspect of the proximal tibia. The three children affected were aged 9, 15 and 27 months respectively. Two required tibial osteotomy, but in one the deformity resolved without treatment. The pathogenesis of the focal lesion remains conjectural; the most likely explanation is that the mesenchymal anlage of the tibial metaphysis has, for unknown reasons, developed abnormally at the insertion of the pes anserinus.

A cortical bone graft on a muscle pedicle was taken from the ulna and transferred to bridge a complete defect of the radius in 16 dogs. In 14 control dogs a free graft was used, that is, one without a muscle pedicle. Union in the group with pedicle grafts was far superior to that in the group with free grafts, mainly because in those with pedicle grafts there was good subperiosteal new bone formation from active viable periosteum. In six of the pedicle grafts the viability of some osteocytes was retained over a 12-week period and in five the graft was almost completely replaced by new bone.

Seven pectoralis major transfers in children suffering from bilateral paralysis of elbow flexion due to arthrogryposis or to trauma are reported. A technique is described in which the muscle is mobilised from the clavicle to allow the tendon of insertion to be attached to the biceps tendon at the elbow. The biceps tendon was found to be present and could be mobilised forwards in all the arthrogrypotic elbows. Subjectively, the results were considered by patients or parents to be very good in six cases and fair in one. Elbow flexion power against gravity and against some resistance was achieved in all patients except one. The overall function was very good in one elbow, good in two, fair in three and poor in only one. The merits of the various procedures described for the restoration of elbow flexion in arthrogryposis are discussed. It is concluded that total pectoralis major transfer by the method described here has given the best results.

Excellent results can be achieved by plating fractures of the shaft of the humerus in patients with multiple injuries. This helps in nursing care and in the management of other injuries. In 38 patients admitted to a regional trauma centre, 39 humeral shaft fractures were plated. There were 27 men and 11 women, with an average age of 31.5 years. Fourteen of the humeral fractures were compound and 20 had significant comminution; 23 were fixed by a plate on the day of admission and all 39 by the twentieth day. Follow-up of 34 fractures showed that all had united, 33 primarily. All patients but one had a fully functional shoulder and no patient with a fractured humerus alone had lost any elbow movement. Complications were rare--one case each of non-union, fixation failure and infection. No permanent nerve injuries were produced at operation. The plating of fractures of the humerus in these circumstances has been shown to produce excellent results and has a place in the management of the patient with multiple injuries.

We report the ulnar impingement syndrome, which is caused by a shortened ulna impinging on the distal radius and causing a painful, disabling pseudarthrosis. Of the 11 cases reported, 10 were due to excision of the distal ulna after injury to the wrist; the other was a result of a growth arrest after a fracture of the distal ulna in a child. The symptoms are a painful, clicking wrist and a weak grip; clinical examination reveals a narrow wrist with pain on compression of the radius and ulna and on forced supination. Radiographs in the majority of cases show scalloping of the distal radius corresponding to the site of impingement. The mechanism by which ulnar impingement occurs after radio-ulnar convergence is illustrated. The plan of management for the young patient with traumatic dysfunction of the distal radio-ulnar joint is discussed; excision of the lower end of the ulna is not advised in such patients.

Ruptures of the calcaneal tendon which present late may be repaired using carbon fibre to induce a neotendon. The operative technique is described and the results of five cases reviewed. The average muscle power obtained was 88% of normal, and the thickness of the neotendon was 148% of that of the normal side. It would appear that this tendon formation in man is comparable to that previously described in sheep.

There are differences of opinion about the pathogenesis of Perthes' disease. All are agreed that it is due to ischaemia, but the cause of this and the size and number of infarctions are in dispute. Through the generosity of the contributors six whole femoral heads and core biopsies of five other cases have been studied radiographically and histologically. The findings ranged from an ischaemic arrest of ossification in the capital articular cartilage without infarction to multiple complete infarctions of the epiphysial bone. The ensuing reparative process contributes to the pathology, which is of a range to warrant grading or grouping.

1. Twenty-one cases of congenital dislocation of the hip were found on examination of 1,881 consecutive neonates on the first day of life, giving an incidence of eleven per 1,000 live births.

2. Insignificant high-pitched "clicks" were noted in 10 per cent of newborn children.

3. Conversion of half of the patients with hip dislocation to normal occurred during the first post-natal week.

4. Joint laxity was not a feature of the newborn with congenital dislocation of the hip.

5. Oestradiol, oestrone and oestriol were estimated in twenty-fourhour urine samples collected from sixteen patients with congenital dislocation of the hip and nineteen matched controls during the first six days of life. No significant differences in oestrogen output between the two groups were found.

6. The hypothesis that congenital dislocation of the hip is a result of an inborn error of oestrogen metabolism in the newborn is not supported.

1. Six cases of malunited anterior Monteggia fracture have been treated, five of them successfully, by open reduction and reconstruction of the orbicular ligament by turning down a slip from the triceps tendon.

2. One relapse occurred after a slight injury; this was because of an unsuitable triceps tendon.

3. A slip from the triceps tendon has retained reduction of the head of the radius in a patient with congenital dislocation of the radial head.

One of the aims of this work was to find criteria by which the quality of bone as a supporting tissue might be judged. This inevitably involves discussion and, if possible, assessment, of the relative importance of the inorganic and organic material of the bone. It is relatively easy to measure the mineral content, and for that reason it has always received more than its due share of attention.

In the present experiment the composition of the ash of all bones was remarkably constant, with a Ca/P ratio of 2. Furthermore, X-ray crystallography showed that the structure of the inorganic material was the same in all cases. The great difficulty of measuring variations in the quality of the organic material which is, of course, protein in nature makes it impossible to say how much it influences bone strength. Since at least 40 per cent. of the bone is collagen, either a quantitative or a qualitative alteration might alter bone strength. X-ray crystallography revealed no qualitative differences in the collagen material of bones of the three groups; so that for the present it would seem safer to assume that alterations in the physical properties of the bones are due to variations in the relative proportions of organic and inorganic constituents (Dawson 1946, Bell et al. 1947).

These experiments show that the three diets produce highly significant differences in the percentage of ash, in S_B, and in E. It is possible that some variations in the percentage of ash are due to variations in the absolute collagen (weight of collagen in unit volume of bone substance); but the range of variation in the percentage of ash leaves no reasonable doubt that differences in percentage ash between the diet groups are due essentially to differences in absolute ash. Presumably the collagen contributes something to the strength of the bone; but the indications are that it plays a minor part and that the relative weakness and flexibility of rachitic bones is due to decrease in the absolute ash content. Within any one diet group, the relation between percentage ash and the other two variables, S_B and E, is masked by other sources of variation such as those associated with the many measurements involved; and thus the correlation between percentage ash and S_B, and also between percentage ash and E, is not significant.

At first sight, the scatter diagrams (Figs. 5 and 6) appear to indicate a correlation between ash and S_B, and between ash and E. Closer inspection shows, however, that the apparent trend is due largely to differences between the means of the diet groups, and that the points within any one group show no such obvious trend. Figure 7 shows that the position with regard to correlation between S_B and E is very different. Here there is an obvious trend within each diet group; the amount of scatter is very much less. Calculation shows that, even when the differences between the means of diet groups is excluded, there is still a significant correlation between S_B and E. The question of the correlation between the three variables is discussed more fully in the addendum to this paper.

Although the "goodness" of a bone is usually judged by its breaking stress, the experimental findings recorded above suggest that it may be assessed equally well on the basis of elastic properties as shown by Young's modulus. Normal bones, group S in these experiments, were elastic up to 79 per cent. of their breaking stress (Table II): the poorer bones of groups R and N were, however, only a little inferior in this respect. In some cases there was no apparent deviation of the load-deflexion curve from a straight line until the bone was about to break. Such a curve was published in the first paper of this series (Bell, Cuthbertson and Orr 1941), but in the light of further experience this curve is scarcely typical. The terminal falling over of the curve is illustrated in Figure 4 and is much more marked in the bones of group R.

While stress at the upper limit of elasticity varies over a wide range in the three groups (Table II and Fig. 4), the strain at this point is remarkably constant at about 1·5 per cent. This same percentage displacement must occur between the molecules of the bone material at the elastic limit—and it may be that, up to this amount of molecular displacement, the deformation is reversible; but that beyond it, plastic changes occur. We have no evidence as to whether the limiting displacement concerns mineral or protein constituents of the bone, or both.

We have already commented on the remarkable strength of bone material (Bell et al., 1941). The breaking stress of normal rat bone is about the same as that of cast iron, and about half that of mild steel. Young's modulus, however, is only one-tenth that of cast iron and one-twentieth that of steel. Thus bone, despite its lightness (specific gravity about 2·5 as compared with 7·9 for iron), is remarkably strong and at the same time more flexible than might be expected. Presumably the biological advantage is that greater flexibility helps to absorb sudden impacts. It is unusual in metallic substances to find the elastic modulus proportional to the strength; this is more characteristic of materials like concrete and timber. Another remarkable property of bone is that it remains elastic up to three-quarters of the breaking stress. Most metals show considerable ductility before reaching their breaking point.

While Young's modulus is of interest, both on its own account and as an index of the quality of the bone, its close association with breaking stress suggests that it might be used to predict the maximum load which a bone can carry safely. Since E, unlike S_B, can be measured without damage, useful information might be gained by measuring the elasticity of living human bones.