Aims. The aim of this study was to investigate the feasibility of application of a 3D-printed megaprosthesis with hemiarthroplasty design for defects of the distal humerus or proximal ulna following tumour resection. Methods. From June 2018 to January 2020, 13 patients with aggressive or malignant tumours involving the distal humerus (n = 8) or proximal ulna (n = 5) were treated by en bloc resection and reconstruction with a 3D-printed megaprosthesis with hemiarthroplasty, designed in our centre. In this paper, we summarize the baseline and operative data, oncological outcome, complication profiles, and functional status of these patients. Results. Preparation of the prosthesis was a mean of 8.0 days (SD 1.5), during which time no patients experienced tumour progression. The mean operating time and intraoperative blood loss were 158.1 minutes (SD 67.6) and 176.9 ml (SD 187.8), respectively. All of the prostheses were implanted successfully. During a mean follow-up of 25.7 months (SD 7.8), no patients died, but four had complications (two superficial wound problems, one temporary palsy of radial nerve, and one dislocation). No aseptic loosening, structural failure, infection, heterotopic ossification, or degenerative arthritis was seen in this study. The mean flexion of the elbow was 119.6° (SD 15.9°) and the mean extension lag was 11.9° (SD 13.8°). The mean Musculoskeletal Tumor Society 93 score and Mayo Elbow Performance Score were 28.4 (SD 0.9) and 97.7 (SD 4.4), respectively. Conclusion. The custom-made, 3D-printed megaprosthesis with hemiarthroplasty is a feasible option for functional reconstruction after resection of a tumour in the distal humerus or proximal ulna. Cite this article: Bone Joint J 2022;104-B(6):747–757

Standard fixation for intra-articular distal humerus fracture is open reduction and internal fixation (ORIF). However, high energy fractures of the distal humerus are often accompanied with soft tissue injuries and or vascular injuries which limits the use of internal fixation. In our report, we describe a highly complex distal humerus fracture that showed promising healing via a ring external fixator. A 26-year-old man sustained a Gustillo Anderson Grade IIIB intra-articular distal humerus fracture of the non-dominant limb with bone loss at the lateral column. The injury was managed with aggressive wound debridement and cross elbow stabilization via a hinged ring external fixator. Post operative wound managed with foam dressing. Post-operatively, early controlled mobilization of elbow commenced. Fracture union achieved by 9 weeks and frame removed once fracture united. No surgical site infection or non-union observed throughout follow up. At 2 years follow up, flexion - extension of elbow is 20°- 100°, forearm supination 65°, forearm pronation 60° with no significant valgus or varus deformity. The extent of normal anatomic restoration in elbow fracture fixation determines the quality of elbow function with most common complication being elbow stiffness. Ring fixator is a non-invasive external device which provides firm stabilization of fracture while allowing for adequate soft tissue management. It provides continuous axial micro-movements in the frame which promotes callus formation while avoiding translation or angulation between the fragments. In appropriate frame design, they allow for early rehabilitation of joint where normal range of motion can be allowed in controlled manner immediately post-fixation. Functional outcome of elbow fracture from ring external fixation is comparable to ORIF due to better rehabilitation and lower complications. Ring external fixator in our patient achieved acceptable functional outcome and fracture alignment meanwhile the fracture was not complicated with common complications seen in ORIF. In conclusion, ring external fixator is as effective as ORIF in treating complex distal humeral fractures and should be considered for definitive fixation in such fractures

Patients and Methods: Between December 2005 until January 2008 34 distal humerus fractures in 33 patients were prospectively documented and treated using the angular-stable LCP distal humerus plate system from Synthes/Switzerland. Patient median age was 54 (min 14/ max 88). Fracture types were classified according to the AO classification. Extraarticular A fractures were documented in 3 (9%) cases, partial intra-articular fractures (type B) were seen in 4 (12%) patients. Complete intraarticular fractures were found in 27 (79%) cases. Three fractures were grade I° open, 6 fractures were grade II° open according to the Gustilo classification. In median after 10 months (min 8/ max 20) follow up was performed. Due to lost to follow up in one patient functional outcome was measured in 32 patients. Functional results were evaluated using the Mayo Elbow Performence Score (MEPS). Results: According to MEPS, predominantly excellent and good results were achieved. The intent of stable fracture fixation to allow early physical therapy was reached in 31 patients. Failure of osteosynthesis making operative revision necessary occurred in 3 patients (1x implant failure, 2x loss of reduction). Mean Mayo Elbow Performance Score was 91 points (min 88.5/ max 100). Mean range of motion for extension/flexion was 110° (min 80/ max 140) and 170° (min 125/max 180) for pronation/supination. Only one patient regained unrestricted extension, mean loss of extension was 21° (min 10/ max 40). Mean Flexion up to 131° was achieved (min 125/ max 140). Postoperative complications were seen in eight cases (implant breakage, delayed union, lost of reduction). Conclusion: Despite postoperative complications and revision surgery, functional results achieved using the angular-stable LCP distal Humerus system are good or excellent in the majority of patients. Through angular-stable and multidirectional screw options fixation of the distal fragment is sufficient and periostal blood supply could be protected. Especially in combination of intraarticular fractures and osteoporotic bone stock the use of the LCP distal Humerus plate system is suitable and permits early physical therapy, promising a benefit for the elbow function

Aims. We review our experience of Coonrad-Morrey total elbow arthroplasty (TEA) for fractures of the distal humerus in non-rheumatoid patients with a minimum of ten years follow-up. Patients and Methods. TEA through a triceps splitting approach was peformed in 37 non-rheumatoid patients for a fracture of the distal humerus between 1996 and 2004. One patient could not be traced and 17 had died before the tenth anniversary of their surgery. This left 19 patients with a minimum follow-up of ten years to form the study group. Of these, 13 patients were alive at the time of final review. The other six had died, but after the tenth anniversary of their elbow arthroplasty. Their clinical and radiological data were included in the study. . Results. The mean follow-up of the 19 patients was 156 months (120 to 210). Two patients in the study group had undergone revision. One further patient had undergone a two-stage revision for infection but died before ten-year follow-up. Six other patients in the study group had evidence of loosening or wear of their bushings. Two were clinically symptomatic and were offered revision surgery. Male patients showed higher incidence of loosening and wear. Survivorship, with revision and definite loosening as end-points, was 89.5% at ten years in those patients followed for a minimum of ten years and 86% in the whole group of 36 patients. Conclusion. This study shows that only 53% of non-rheumatoid patients who undergo TEA for a fracture of the distal humerus survive to the tenth anniversary of their index procedure. For those that survive, TEA provides acceptable outcomes in terms of function and implant survival. Take home message: The surgeons undertaking these procedures should be aware of the long-term revision rates and also the gender difference in the rates of loosening. Cite this article: Bone Joint J 2016;98-B:381–6

Abstract. Introduction. Intra-articular distal humerus OTA type C fractures are challenging to treat. When osteosynthesis is not feasible one can choose to do a primary arthroplasty of elbow or manage non-operatively. The indications for treatment of this fracture pattern are evolving. Objectives. We present our outcomes and complications when this cohort of patients was managed with either open reduction internal fixator (ORIF), elbow arthroplasty or non-operatively. Methods. Retrospective study to include OTA type C2 and C3 fracture distal humerus of 36 patients over the age of 50 years managed with all the three modalities. Patient's clinical notes and radiographs were reviewed. Results. Between 2016 and 2022, 21 patients underwent ORIF – group 1, 10 patients were treated with arthroplasty – group 2 and 5 were managed conservatively- group 3. The mean age of patients was 62 years in group 1, 70 years in group 2 and 76 years in group 3. The mean range of movement (ROM) arc achieved in the group 1 & 2 was 103 while group 3 was 68. At least follow up was 6 months. 5 patients in group 1 underwent metalwork removal and 2 patients in group 3 under arthroplasty. Conclusion. The outcomes of arthroplasty and ORIF are comparable, but reoperation rates and stiffness were higher in ORIF and conservative group. Surgeon choice and patient factors play important role in decision towards choosing treatment modality. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

The distal humerus represents 1% of all primary bone tumours. Endoprosthetic replacement can potentially improve function and provide good pain relief. We present out experience with the custom made Stanmore elbow endoprosthesis used after resection of malignant tumours of the distal humerus. Between 1970–2009 we carried out 19 endoprosthetic replacments for malignant tumours of the distal humerus. 10 were a result of metastasis and 9 were primary bone tumours. 7 patients had a pathological fracture as their first presentation and 3 had pathological fractures after the diagnosis was made. 11 patients died between 3 months to 16 year following surgery. The mean survival of the patient group was 7.1 years (range 3 months to 37 years). 4 patients underwent a revision EPR and one patient underwent two revision EPR's due to loosening. Two patients underwent maintenance procedures (rebushing) due to wear of the poly bushing. We have had no revisions since the design of hte implant was changed to a floppy hinge design. One patient underwent an above elbow amputation four years after surgery due to local recurrence. There were no early post operative infections. One patient developed a sinus requiring multiple wound explorations, one year after insertion of the endoprosthesis for a sarcoma. This patient was infection free till the time of death 3 years later. There were no nerve palsies, periprosthetic fractures or wound problems. The mean TES score was 72% (59–78%) in the surviving patients at review. As the majority of the patients were implanted for metastatic disease the initial reliablity and low complication rate of the procedure, in our series, confirms that this is a suitable reconstruction for patients in significant metastatic pain from a destructive lesion of the distal humerus, rapidly restoring function and relieving pain in a predictable manner

Advancements in treating distal humerus fractures. We will review and discuss approaches to the elbow to treat different types of fractures. We will discuss the role of soft tissue structures and how they affect elbow function. During this session, we will review the latest techniques for treating the complex articular fractures of the distal humerus to include capitellar and trochlear fractures. Techniques presented will address fixation, reconstruction, and salvaging of complex distal humerus fractures

Only 1% of all primary bone tumours are situated in the distal humerus. Destruction of the distal humerus by tumour is rare and reconstruction of the distal humerus is challenging. Because of the amount of bone loss following tumour excision, excision arthroplasty or arthrodesis is impossible and hence some form of reconstruction is usually required. Allograft reconstruction and hemiarthroplasty are uncommon and lead to an unpredictable outcome. Ten patients underwent endoprosthetic replacement of the distal humerus for bone tumours over a thirty one-year period. There were 8 primary and 2 secondary tumours and male to female ratio was 2:3. Average age of the patients was 47.5 years (15–76 years). Mean follow up was 8 years (9 months - 31 years). Four patients required further surgery, three having revision for asceptic loosening and two of these and one other later needing a rebushing. There were no permanent nerve palsies, infections, local recurrences or mechanical failures of the implant. Four patients died of their disease between 12 and 71 months after operation, all with their prosthesis working normally. Average flexion deformity was 15 degrees (0–35) and average flexion of these patients was 115 degrees (110–135). The average TES Score for these patients was 73% (29% to 93%). The activities which the patients found to be no problem (TES score more than 4.5 out of 5) were: brushing hair, drinking from a glass, putting on make up or shaving, picking up small items, turning a key in a lock, doing light household chores and socialising with friends, whilst activities that proved difficult (TES score less than 3 out of 5) were: gardening and lifting a box to an overhead shelf. Pain was not a problem and only 1 of the surviving patients reported ever having to use regular analgesics. Conclusions: Endoprosthetic replacement of the distal humerus and elbow joint is a satisfactory method of dealing with these unusual tumours in the long term

Fractures of the distal humerus present a challenge. The fractures are often intra-articular and the bone osteoporotic. The elbow tolerates surgery and immobilisation poorly, and it is difficult to secure rigid fixation. Union must be achieved and elbow motion preserved. The results of fixation of fractures of the distal humerus are unpredictable. Fixation with two plates at 90° angles to one another has become the standard against which all other treatment is measured. Following up patients for a mean of 24 months, the author conducted a prospective study evaluating posterior plating of the two columns of the distal humerus with reconstruction plates and intercondylar fixation. Between 1996 and 2000, 18 women and seven men with unilateral intra-articular fractures of the distal humerus were treated. Their mean age was 46 years (35 to 71). The fractures were classified according to the AO classification: there were 22 type-CII and three type-CIII. Four fractures were compound. One of two posterior approaches was used, either through the triceps aponeurosis or using an olecranon osteotomy. Postoperative management included prophylactic intravenous antibiotics for 48 hours and a posterior splint for 7 to 10 days. Active movement commenced once sutures were removed, but patients avoided active or resisted extension for six weeks. The mean time to union was 16 weeks. Patients attained a mean range of elbow movement of 105° (35° to 135°). One patient developed superficial sepsis but recovered after treatment with antibiotics. One patient with a compound injury developed a deep infection, which required multiple debridements, gentamycin beads and bone grafting to achieve union. There were no implant failures or cases of nerve paralysis. This study demonstrated no differences in functional outcome between triceps aponeurosis or olecranon osteotomy approach. Union and satisfactory functional results were achieved with posterior plating of the columns and intercondylar fixation

Abstract. Objectives. Operative management of distal humerus fractures is challenging. In the past, plates were manually contoured intraoperatively, however this was associated with high rates of fixation failure, nonunion and metalwork removal. Anatomically pre-contoured distal humerus locking plates have since been developed. Owing to the rarity of distal humeral fractures, literature regarding outcomes of anatomically pre-contoured locking plates is lacking and patient numbers are often small. The purpose of this study is to investigate the outcomes of these patients. Methods. We retrospectively identified patients with distal humeral fractures treated at our institution from 2009–2018. Inclusion criteria were patients with a distal humeral fracture, who underwent two-column plate fixation with anatomically pre-contoured locking plates. Clinical records and radiographs were reviewed to elicit outcome measures, including range of motion, complications and reoperation rate. Results. We identified 50 patients with mean age of 55 years (range 17–96 years). Mean length of follow up was 5.2 years. AO fracture classification Type A occurred most frequently (46%), followed by Type B (22%) and Type C (32%). Low energy mechanisms of injury predominated in 72% of patients. Mean time from injury to fixation was seven days. Mean range of motion at the elbow was 13–123o postoperatively. The overall reoperation rate was 22%, the majority of which required subsequent removal of prominent metalwork (18%). The incidence of nonunion, heterotopic ossification, deep infection and neuropathy requiring decompression was 2% each. Fixation failure occurred in only one patient however the fracture went on to heal. Conclusions. Previously reported reoperation rates with manually contoured plates were as high as 44%, which is twice our reported rate. Modern locking plates are no longer subject to implant failure (previously 27% reported metalwork failure rate). Likewise, heterotopic ossification and non-union have also reduced, highlighting that modern plates have significantly improved overall patient outcomes. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Purpose: The supracondylar fractures of the distal humerus are the second most frequent fractures of the developing skeleton. Also their immediate and late complications are very often. The aim of this study is to describe their neurological complications. Material – methods: In our department 178 children were admitted with supracondylar fracture of the distal humerus during the period 1998–2002. Their age ranged from 2 to 16 years of age (the average was 7 years old, 63 girls and 115 boys). Forty-six patients were treated conservatively and 132 surgically. Neurological complications were appeared in 18 patients that had, according to Gartland classification, II and III type fractures. Manipulations for closed reduction had been made to 6 of them. Neurological deficit of the median nerve appeared to 10 patients, of the radial nerve to 6 patients and of ulnar nerve to 2 patients. The treatment of the fractures was surgical (open reduction, internal fixation with Kirschner wires and immobilization with a long arm cast for 4 weeks). The treatment of the neurological complications was conservative (free mobilization of the elbow was followed after the removal of the arm cast and Kirschner’s wires). Results: The results of the conservative treatment of the neurological complications of the supracondylar fractures of the distal humerus were excellent and the surgical exploration on the injured nerve was not necessary on any patient. The function of the nerves recovered completely in 2–3 months after the elbow’s fracture. Conclusion: The prognosis on the neurological complications of the upper limbs due to supracondylar fracture of the distal humerus is very good. They are successfully treated conservatively and the surgical exploration on the injured nerve is rarely necessary

Three 3mm transverse slices were sectioned from the distal cancellous region of seven fresh-frozen cadaveric humerii. Each slice was marked with a 3x3mm grid, and subjected to compressive testing using a flat cylindrical indenter (1.6mm diameter). Indentation modulus and strength were calculated for each site, and pooled into nine anatomically-defined regions. The most distal slice had higher moduli values (p< 0.05), and the posterior capitellar region had lower moduli values (p< 0.05). There were no slice or regional differences in strength. This suggests that surgical procedures requiring cancellous fixation utilize the most distal aspect of the humerus while avoiding the posterior capitellum. To quantify the indentation strength and modulus of distal humeral cancellous bone, and identify any regional variations. Cancellous bone modulus in the distal humerus decreases from distal to proximal. The posterior capitellum has a lower modulus than the other regions of the distal humerus. The influence of slice depth emphasizes the importance of minimizing the amount of bone removed during prosthetic replacement. Regional variations in modulus suggest that the posterior capitellum should be avoided during fixation of implants or placement of screws. Three 3mm transverse cancellous bone slices obtained from the distal end of each of seven fresh-frozen cadaveric specimens were subjected to compressive testing using a materials testing machine with a 1.6mm flat cylindrical indenter. Testing was performed in a 3x3mm grid. The indentation modulus and local strength were calculated for each test site, and then averaged into nine regions defined by the capitellum, medial and lateral trochlea, and anterior, central and posterior sections for each slice. Mean modulus was found to be 309.8±242.0 MPa (range: 2.9–1041.7 MPa). Yield strength averaged 4.4±2.5 MPa (range: 0.6–16.3 MPa). The highest modulus was found in the distal-most slice (p< 0.05). The lowest modulus region was the posterior capitellum (p< 0.05). There were no differences in strength between slices or across the nine regions. A comparison with proximal tibial cancellous bone properties suggests the distal humerus may carry loads approaching 30% of those at the knee, assuming that bone adapts to stress magnitudes. Funding: Natural Sciences and Engineering Research Council; University of Western Ontario

Purpose: The purpose of this study was to evaluate a new ONI Elbow Plate System for intra-articular fractures of the distal humerus in the elderly. Methods: 10 elder patients with complete intra-articular distal humerus fractures were treated by our new fixation system. The mean age of our patients was 76 years old (range 70 to 88 years). According to the AO/ASIF system, 6 cases were type C1, three cases were C2 and one case was C3. The ONI transcondylar plate conforms to the anatomical contour of the lateral column of the distal humerus and a locking mechanism between the plate portion and the transcondylar screw and the ONI medial plate conforms to the anatomical contour of the medial one (ONI Elbow Plate System). In all cases the ONI transcondylar plate was used at the lateral side of the fracture site, and either a cannulated cancellous screw (n=3) or an AO one-third tubular plate (n=4) or the ONI medial plate (n=3) at the medial side. The mean period of follow up was 32 months (24 to 48 months). Results: In all of the 10 cases, complete union was seen on radiographs, and alignment was almost maintained postoperatively. The assessment of results according to the modified Cassebaum’s rating score was 90.4. There were no cases of nonunion or malunion. Conclusion: Our data showed that the ONI Elbow System for treatment of this fracture in the elderly produced consistently good results even in cases with a small osteoporotic fragment of the distal humerus

A single antegrade Rush nail was used to treat 37 fractures of the distal humerus extending to the olecranon fossa and up to 6.5 cm proximal to it. In order to stabilise the fracture, the bent tip of the Rush nail was directed into the lateral epicondylar ridge. This gave immediate stability. All the fractures united without residual stiffness of the shoulder or elbow

Between 1995 and 2000, 19 consecutive patients with fractures of the distal humerus were treated by primary total elbow replacement using the Coonrad-Morrey prosthesis. No patient had inflammatory or degenerative arthritis of the elbow. The mean age at the time of injury was 73 years (61 to 95). According to the AO classification, 11 patients had suffered a C3 injury, two a B3 and two an A3. One fracture was unclassified. Two patients died from unrelated causes and one was unable to be assessed because of concurrent illness. The mean time to follow-up was three years (1 to 5.5). At follow-up 11 patients (68%) reported no pain, four (25%) had mild pain with activity and one had mild pain at rest. The mean flexion arc was 24° to 125°. The mean supination was 90° (70 to 100) and pronation 70° (50 to 110). No elbow was unstable. The mean Disabilities of the Arm, Shoulder and Hand score was 23 (0.92 to 63.3) and the mean Mayo elbow performance score was 93 (80 to 100). Of the 16 patients, 15 were satisfied with the outcome. Radiological evaluation revealed only one patient with a radiolucent line at the cement-bone interface. It was between 1 and 2 mm in length, was present on the initial postoperative radiograph and was non-progressive at the time of follow-up. Primary total elbow arthroplasty is an acceptable option for the management of comminuted fractures of the distal humerus in elderly patients when the configuration of the fracture and the quality of the bone make reconstruction difficult

Aims: The aim of this paper is to present our experience in the treatment of comminuted fractures of the distal humerus. Our surgical target was to reconstruct all three edges of the triangle to achieve the best functional result. Methods: In a period of 5 years, 28 patients who suffered a comminuted fracture of the distal humerus were operated with open reduction and internal fixation. Those were 21 males and 7 females with a mean age of 25 years. According to AO/ASIF classification there were 5 patients with A1 fracture, 3 pts A2, 6 B2, 8 B3, 3 C1, 1 C2 and 2 pt C3. In 25 patients was applied posterior approach after transolecranon osteotomy and lateral approach in the rest 3 patients. All patients were evaluated clinically and radiologically. Results: The mean time of follow up was 12 months. In 7 patients full range of motion was achieved, in 8 functional range of motion and in 4 limited but in functional range. The mean range of elbow flexion – extension arc was 115°. Complications included postoperative paresis of ulnar or radial nerve, ectopic bone formation and material failure. Conclusions: The comminuted intraarticular fractures of the distal humerus demand careful preoperative planning, extensive but atraumatic exposures and the use of the appropriate fixation materials for each case. Low complication rate and excellent functional results are ensured

Introduction: Treatment and outcome of patients with rheumatoid arthritis and distal humerus fractures is not well established. Methods: Between 1982 and 2002 twenty-four elbows in twenty-two patients (eleven men, eleven women) treated for acute distal humerus fractures were retrospectively reviewed. The average age at time of the fracture was 64 years. Eleven elbows were immediately treated with a total elbow arthroplasty (TEA) type Coonrad-Morrey (CM), six elbows had underwent open reduction and internal fixation (ORIF), and seven elbows were referred to our institution after failed ORIF elsewhere and were revised with an TEA (CM). Results: At an average follow-up of 52 months the Mayo Elbow Performance Score (MEPS) averaged in the eleven elbows with an immediate TEA 96 points and in the six elbows with ORIF 93 points (p=0.79). In the seven elbows with TEA after failed ORIF there was a trend towards a less favorable outcome (MEPS: 86 points) but the differences was not significant compared to immediate TEA (p=0.31) and ORIF (p=0.53). Patients with failed ORIF and a subsequent TEA had an average of 3 operation per elbow with one patient ending in elbow resection after an infected TEA. Patients with immediate TEA had an average of 1.3 operations and patients with successful ORIF 1.2 interventions. Discussion and Conclusion: Distal humerus fractures in patients with rheumatoid arthritis can be treated successfully with an immediate TEA or ORIF. There is a trend towards a poorer clinical outcome in patients with TEA after failed ORIF

We reviewed 20 patients who had undergone a Coonrad-Morrey total elbow arthroplasty after resection of a primary or metastatic tumour from the elbow or distal humerus between 1980 and 2002. Eighteen patients underwent reconstruction for palliative treatment with restoration of function after intralesional surgery and two after excision of a primary bone tumour. The mean follow-up was 30 months (1 to 192). Five patients (25%) were alive at the final follow-up; 14 (70%) had died of their disease and one of unrelated causes. Local control was achieved in 15 patients (75%). The mean Mayo Elbow Performance Score improved from 22 (5 to 45) to 75 points (55 to 95). Four reconstructions (20%) failed and required revision. Seven patients (35%) had early complications, the most frequent being nerve injury (25%). There were no infections or wound complications although 18 patients (90%) had radiotherapy, chemotherapy or both. The Coonrad-Morrey total elbow arthroplasty provides good relief from pain and a good functional outcome after resection of tumours of the elbow. The rates of complications involving local recurrence of tumour (25%) and nerve injury (25%) are of concern

Ten patients underwent endoprosthetic replacement of the distal humerus for bone tumours over a period of 30 years. There were eight primary and two secondary tumours in four men and six women with a mean age of 47.5 years (15 to 76). The mean follow-up was eight years (9 months to 31 years). Four patients required further surgery, three having revision for aseptic loosening; two of these and one other later needing a rebushing. There were no cases of postoperative nerve palsy, infection, local recurrence or mechanical failure of the implant. Four patients died from their disease, all with the prosthesis functioning satisfactorily. At follow-up the mean flexion deformity of the elbow was 15° (0 to 35) and the mean range of flexion was 115° (110 to 135). The functional results showed a mean Toronto extremity salvage score of 73% of normal. Endoprosthetic replacement of the distal humerus and elbow is a satisfactory method of treating these rare tumours

Introduction:. Distal humerus fractures as well as elbow fracture dislocation are often accompanied by soft tissue damage that warrants early fixation with an external fixator. The distal humerus is a hazardous area for placement of an external fixator due to the close proximity of the radial nerve to the humerus in this area. No known safe zone has been identified on the lateral border of the humerus to avoid radial nerve damage. The aim of this study was to record the incidence of radial nerve damage by placing two 4 mm pins into the humerus and to note the relation of the nerve to the pins. Methods:. Two 4 mm pins used to fix an external fixator were drilled into the lateral border of the humerus at points 100 mm and 70 mm proximal to the lateral epicondyle of both arms of 39 cadavers. The 30 mm interval between the pins is the interval between the pins in a pinblock of a commonly-used external fixator. The arms were dissected by medical students and the incidence of radial nerve damage was recorded. Statistical analysis was done using a Fischer's exact test to identify the incidence of nerve damage relative to pin insertion. The number of damaged nerves was compared to the number of non-damaged nerves. A design based Chi Square test was carried out to test left and right arms. The proportions of interest were estimated along a 95% confidence interval. Results:. The radial nerve was hit (damaged) by 56.4% of the proximal and 20.5% of the distal pins. The radial nerve ran posterior to the proximal pin in 2.57% of arms and 0% to the distal pin. Conclusion:. Although no clear safe zone could be established, pins should be placed closer than 100 mm from the lateral epicondyle and as posterior on the humerus as possible to minimize the risk for radial nerve damage. Keywords: Radial nerve, external fixation, humerus fractures