Aims

Rotator cuff muscle atrophy and fatty infiltration affect the clinical outcomes of rotator cuff tear patients. However, there is no effective treatment for fatty infiltration at this time. High-intensity interval training (HIIT) helps to activate beige adipose tissue. The goal of this study was to test the role of HIIT in improving muscle quality in a rotator cuff tear model via the β3 adrenergic receptor (β3AR).

Aims

This study aimed to define the histopathology of degenerated humeral head cartilage and synovial inflammation of the glenohumeral joint in patients with omarthrosis (OmA) and cuff tear arthropathy (CTA). Additionally, the potential of immunohistochemical tissue biomarkers in reflecting the degeneration status of humeral head cartilage was evaluated.

Aims

To evaluate if union of clavicle fractures can be predicted at six weeks post-injury by the presence of bridging callus on ultrasound.

Aims

The aim of this study was to compare the pain caused by the application of a tourniquet after exsanguination of the upper limb with that occurring after simple elevation.

Methods

Between 2005 and 2012, 50 patients (23 female, 27 male) with nonunion of the humeral shaft were included in this retrospective study. The mean age was 51.3 years (14 to 88). The patients had a mean of 1.5 prior operations (sd 1.2;1 to 8).

All patients were assessed according to a specific risk score in order to devise an optimal and individual therapy plan consistent with the Diamond Concept. In 32 cases (64%), a change in the osteosynthesis to an angular stable locking compression plate was performed. According to the individual risk an additional bone graft and/or bone morphogenetic protein-7 (BMP-7) were applied.

Objectives

Traumatic brachial plexus injury causes severe functional impairment of the arm. Elbow flexion is often affected. Nerve surgery or tendon transfers provide the only means to obtain improved elbow flexion. Unfortunately, the functionality of the arm often remains insufficient. Stem cell therapy could potentially improve muscle strength and avoid muscle-tendon transfer. This pilot study assesses the safety and regenerative potential of autologous bone marrow-derived mononuclear cell injection in partially denervated biceps.

This study was performed to determine whether pure cancellous bone graft and Kirschner (K-) wire fixation were sufficient to achieve bony union and restore alignment in scaphoid nonunion. A total of 65 patients who underwent cancellous bone graft and K-wire fixation were included in this study. The series included 61 men and four women with a mean age of 34 years (15 to 72) and mean delay to surgery of 28.7 months (3 to 240). The patients were divided into an unstable group (A) and stable group (B) depending on the pre-operative radiographs. Unstable nonunion was defined as a lateral intrascaphoid angle > 45°, or a radiolunate angle > 10°. There were 34 cases in group A and 31 cases in group B. Bony union was achieved in 30 patients (88.2%) in group A, and in 26 (83.9%) in group B (p = 0.439). Comparison of the post-operative radiographs between the two groups showed no significant differences in lateral intrascaphoid angle (p = 0.657) and scaphoid length (p = 0.670) and height (p = 0.193). The radiolunate angle was significantly different (p = 0.020) but the mean value in both groups was < 10°. Comparison of the dorsiflexion and palmar flexion of movement of the wrist and the mean Mayo wrist score at the final clinical visit in each group showed no significant difference (p = 0.190, p = 0.587 and p = 0.265, respectively). Cancellous bone graft and K-wire fixation were effective in the treatment of stable and unstable scaphoid nonunion.

Cite this article: Bone Joint J 2013;95-B:809–14.

Objectives

To report the five-year results of a randomised controlled trial examining the effectiveness of arthroscopic acromioplasty in the treatment of stage II shoulder impingement syndrome.

Objectives

The aim of this study was to determine whether there is any significant difference in temporal measurements of pain, function and rates of re-tear for arthroscopic rotator cuff repair (RCR) patients compared with those patients undergoing open RCR.

Impingement syndrome in the shoulder has generally been considered to be a clinical condition of mechanical origin. However, anomalies exist between the pathology in the subacromial space and the degree of pain experienced. These may be explained by variations in the processing of nociceptive inputs between different patients. We investigated the evidence for augmented pain transmission (central sensitisation) in patients with impingement, and the relationship between pre-operative central sensitisation and the outcomes following arthroscopic subacromial decompression.

We recruited 17 patients with unilateral impingement of the shoulder and 17 age- and gender-matched controls, all of whom underwent quantitative sensory testing to detect thresholds for mechanical stimuli, distinctions between sharp and blunt punctate stimuli, and heat pain. Additionally Oxford shoulder scores to assess pain and function, and PainDETECT questionnaires to identify ‘neuropathic’ and referred symptoms were completed. Patients completed these questionnaires pre-operatively and three months post-operatively.

A significant proportion of patients awaiting subacromial decompression had referred pain radiating down the arm and had significant hyperalgesia to punctate stimulus of the skin compared with controls (unpaired t-test, p < 0.0001). These are felt to represent peripheral manifestations of augmented central pain processing (central sensitisation).

The presence of either hyperalgesia or referred pain pre-operatively resulted in a significantly worse outcome from decompression three months after surgery (unpaired t-test, p = 0.04 and p = 0.005, respectively).

These observations confirm the presence of central sensitisation in a proportion of patients with shoulder pain associated with impingement. Also, if patients had relatively high levels of central sensitisation pre-operatively, as indicated by higher levels of punctate hyperalgesia and/or referred pain, the outcome three months after subacromial decompression was significantly worse.

Mason type III fractures of the radial head are treated by open reduction and internal fixation, resection or prosthetic joint replacement. When internal fixation is performed, fixation of the radial head to the shaft is difficult and implant-related complications are common. Furthermore, problems of devascularisation of the radial head can result from fixation of the plate to the radial neck.

In a small retrospective study, the treatment of Mason type III fractures with fixation of the radial neck in 13 cases (group 2) was compared with 12 cases where no fixation was performed (group 1). The mean clinical and radiological follow-up was four years (1 to 9). The Broberg-Morrey index showed excellent results in both groups. Degenerative radiological changes were seen more frequently in group 2, and removal of the implant was necessary in seven of 13 cases.

Post-operative evaluation of these two different techniques revealed similar ranges of movement and functional scores. We propose that anatomical reconstruction of the radial head without metalwork fixation to the neck is preferable, and the outcome is the same as that achieved with the conventional technique. In addition degenerative changes of the elbow joint may develop less frequently, and implant removal is not necessary.

The aim of this study was to investigate genetic influences on the development and progression of tears of the rotator cuff. From a group of siblings of patients with a tear of the rotator cuff and of controls studied five years earlier, we determined the prevalence of tears of the rotator cuff with and without associated symptoms using ultrasound and the Oxford Shoulder Score.

In the five years since the previous assessment, three of 62 (4.8%) of the sibling group and one of the 68 (1.5%) controls had undergone shoulder surgery. These subjects were excluded from the follow-up.

Full-thickness tears were found in 39 of 62 (62.9%) siblings and in 15 of 68 (22.1%) controls (p = 0.0001). The relative risk of full-thickness tears in siblings as opposed to controls was 2.85 (95% confidence interval (CI) 1.75 to 4.64), compared to 2.42 (95% CI 1.77 to 3.31) five years earlier. Full-thickness tears associated with pain were found in 30 of 39 (76.9%) tears in the siblings and in eight of 15 (53.3%) tears in the controls (p = 0.045). The relative risk of pain associated with a full-thickness tear in the siblings as opposed to the controls was 1.44 (95% CI 2.04 to 8.28) (p = 0.045).

In the siblings group ten of 62 (16.1%) had progressed in terms of tear size or development compared to one of 68 (1.5%) in the control group which had increased in size.

Full-thickness rotator cuff tears in siblings are significantly more likely to progress over a period of five years than in a control population. This implies that genetic factors have a role, not only in the development but also in the progression of full-thickness tears of the rotator cuff.

We have carried out a prospective double-blind randomised controlled trial to compare the efficacy of a single subacromial injection of the non-steroidal anti-inflammatory drug, tenoxicam, with a single injection of methylprednisolone in patients with subacromial impingement. A total of 58 patients were randomly allocated into two groups. Group A received 40 mg of methylprednisolone and group B 20 mg of tenoxicam as a subacromial injection along with lignocaine. The Constant-Murley shoulder score was used as the primary outcome measure and the Disability of Arm, Shoulder and Hand (DASH) and the Oxford Shoulder Score (OSS) as secondary measures. Six weeks after injection the improvement in the Constant-Murley score was significantly greater in the methylprednisolone group (p = 0.003) than in the tenoxicam group. The improvement in the DASH score was greater in the steroid group and the difference was statistically significant and consistent two (p < 0.01), four (p < 0.01) and six weeks (p < 0.020) after the injection. The improvement in the OSS was consistently greater in the steroid group than in the tenoxicam group. Although the difference was statistically significant at two (p < 0.001) and four (p = 0.003) weeks after the injection, it was not at six weeks (p = 0.055). Subacromial injection of tenoxicam does not offer an equivalent outcome to subacromial injection of corticosteroid at six weeks. Corticosteroid is significantly better than tenoxicam for improving shoulder function in tendonitis of the rotator cuff after six weeks.

Mechanical loosening which begins with early-onset migration of the prosthesis is the major reason for failure of the Souter-Strathclyde elbow replacement. In a prospective study of 18 Souter-Strathclyde replacements we evaluated the patterns of migration using roentgen stereophotogrammetric analysis. We had previously reported the short-term results after a follow-up of two years which we have now extended to a mean follow-up of 8.2 years (1 to 11.3). Migration was assessed along the co-ordinal axes and overall micromovement was expressed as the maximum total point movement. The alignment of the prosthesis and the presence of radiolucent lines were examined on conventional standardised radiographs.

All the humeral components showed increased and variable patterns of migration at the extended follow-up and four humeral components were revised. The maximum total point movement at two years in the revised prostheses was 1.8 mm (sd 1.0) and in the non-revised 0.7 mm (sd 0.5, p = 0.01). Most humeral components migrated into external rotation resulting in an anterior and varus tilt. The ulnar components remained stable.

We randomised 79 patients (84 hands, 90 fingers) with Dupuytren’s contracture of the proximal interphalangeal joint to have either a ‘firebreak’ skin graft (39 patients, 41 hands, 44 fingers) or a fasciectomy (40 patients, 43 hands, 46 fingers) if, after full correction, the skin over the proximal phalanx could be easily closed by a Z-plasty. Patients were reviewed after three, six, 12, 24 and 36 months to note any complications, the range of movement and recurrence. Both groups were similar in regard to age, gender and factors considered to influence the outcome such as bilateral disease, family history, the presence of diabetes, smoking and alcohol intake.

The degree of contracture of the metacarpophalangeal and interphalangeal joints of the operated fingers was similar in the two groups and both were comparable in terms of grip strength, range of movement and disability at each follow-up. The recurrence rate was 12.2%.

We did not identify any improvement in correction or recurrence of contracture after firebreak dermofasciectomy up to three years after surgery.

There are no long-term published results on the survival of a third-generation cemented total shoulder replacement. We describe a clinical and radiological study of the Aequalis total shoulder replacement for a minimum of ten years. Between September 1996 and May 1998, 39 consecutive patients underwent a primary cemented total shoulder replacement using this prosthesis. Data were collected prospectively on all patients each year, for a minimum of ten years, or until death or failure of the prosthesis. At a follow-up of at least ten years, 12 patients had died with the prosthesis intact and two had emigrated, leaving 25 available for clinical review. Of these, 13 had rheumatoid arthritis and 12 osteoarthritis. One refused radiological review leaving 24 with fresh radiographs.

Survivorship at ten years was 100% for the humeral component and 92% for the glenoid component. The incidence of lucent lines was low. No humeral component was thought to be at risk and only two glenoid components. The osteoarthritic group gained a mean 65° in forward flexion and their Constant score improved by a mean 41.4 points (13 to 55). The rheumatoid group gained a mean of 24° in flexion and their Constant score improved by 29.4 points. This difference may have been due to failure of the rotator cuff in 75% of the patients with rheumatoid arthritis.

Thus a third-generation total shoulder replacement gives an excellent result in patients with osteoarthritis and an intact rotator cuff. Patients with rheumatoid arthritis have a 75% risk of failure of the rotator cuff at ten years.

In order to compare the outcome from surgical repair and physiotherapy, 103 patients with symptomatic small and medium-sized tears of the rotator cuff were randomly allocated to one of the two approaches. The primary outcome measure was the Constant score, and secondary outcome measures included the self-report section of the American Shoulder and Elbow Surgeons score, the Short Form 36 Health Survey and subscores for shoulder movement, pain, strength and patient satisfaction. Scores were taken at baseline and after six and 12 months by a blinded assessor. Nine patients (18%) with insufficient benefit from physiotherapy after at least 15 treatment sessions underwent secondary surgical treatment.

Analysis of between-group differences showed better results for the surgery group on the Constant scale (difference 13.0 points, p − 0.002), on the American Shoulder and Elbow surgeons scale (difference 16.1 points, p < 0.0005), for pain-free abduction (difference 28.8°, p = 0.003) and for reduction in pain (difference on a visual analogue scale −1.7 cm, p < 0.0005).

We report a randomised controlled trial to examine the effectiveness and cost-effectiveness of arthroscopic acromioplasty in the treatment of stage II shoulder impingement syndrome. A total of 140 patients were randomly divided into two treatment groups: supervised exercise programme (n = 70, exercise group) and arthroscopic acromioplasty followed by a similar exercise programme (n = 70, combined treatment group). The main outcome measure was self-reported pain on a visual analogue scale of 0 to 10 at 24 months, measured on the 134 patients (66 in the exercise group and 68 in the combined treatment group) for whom endpoint data were available.

An intention-to-treat analysis disclosed an improvement in both groups but without statistically significant difference in outcome between the groups (p = 0.65). The combined treatment was considerably more costly.

Arthroscopic acromioplasty provides no clinically important effects over a structured and supervised exercise programme alone in terms of subjective outcome or cost-effectiveness when measured at 24 months. Structured exercise treatment should be the basis for treatment of shoulder impingement syndrome, with operative treatment offered judiciously until its true merit is proven.

In a prospective randomised study we compared the results of arthroscopic subacromial bursectomy alone with debridement of the subacromial bursa followed by acromioplasty. A total of 57 patients with a mean age of 47 years (31 to 60) suffering from primary subacromial impingement without a rupture of the rotator cuff who had failed previous conservative treatment were entered into the trial. The type of acromion was classified according to Bigliani. Patients were assessed at follow-up using the Constant score, the simple shoulder test and visual analogue scores for pain and functional impairment. One patient was lost to follow-up.

At a mean follow-up of 2.5 years (1 to 5) both bursectomy and acromioplasty gave good clinical results. No statistically significant differences were found between the two treatments. The type of acromion and severity of symptoms had a greater influence on the clinical outcome than the type of treatment. As a result, we believe that primary subacromial impingement syndrome is largely an intrinsic degenerative condition rather than an extrinsic mechanical disorder.

The aim of this study was to define the microcirculation of the normal rotator cuff during arthroscopic surgery and investigate whether it is altered in diseased cuff tissue.

Blood flow was measured intra-operatively by laser Doppler flowmetry. We investigated six different zones of each rotator cuff during the arthroscopic examination of 56 consecutive patients undergoing investigation for impingement, cuff tears or instability; there were 336 measurements overall.

The mean laser Doppler flowmetry flux was significantly higher at the edges of the tear in torn cuffs (43.1, 95% confidence interval (CI) 37.8 to 48.4) compared with normal cuffs (32.8, 95% CI 27.4 to 38.1; p = 0.0089). It was significantly lower across all anatomical locations in cuffs with impingement (25.4, 95% CI 22.4 to 28.5) compared with normal cuffs (p = 0.0196), and significantly lower in cuffs with impingement compared with torn cuffs (p < 0.0001).

Laser Doppler flowmetry analysis of the rotator cuff blood supply indicated a significant difference between the vascularity of the normal and the pathological rotator cuff. We were unable to demonstrate a functional hypoperfusion area or so-called ‘critical zone’ in the normal cuff. The measured flux decreases with advancing impingement, but there is a substantial increase at the edges of rotator cuff tears. This might reflect an attempt at repair.

We reviewed the outcome of arthroscopic stabilisation of anterior glenohumeral instability in young adults using the transglenoid suture technique. A questionnaire was sent to 455 consecutive patients who had undergone this procedure between 1992 and 2000. Of these, 312 patients (68.5%) with 313 affected shoulders and a mean age of 20 years (18 to 28) responded.

Outcome was determined by the number of re-dislocations or, in patients who had not re-dislocated, by the disease-specific quality of life as measured by the Western Ontario Shoulder Instability index. During a mean follow-up of 6.4 years (1 to 14), 177 patients (56%) sustained a re-dislocation, including 70 who required a further operation. In 136 patients (44%) who reported neither re-dislocation nor re-operation, the index scores were good (median 90.4%; 28.9% to 100%). No significant peri- or pre-operative predictors of re-dislocation or re-operation were found.

We found a high rate of re-dislocation after transglenoid suture repair in young, physically active patients.

We report the outcome at a mean of 93 months (73 to 110) of 71 patients with an acute fracture of the scaphoid who were randomised to Herbert screw fixation (35) or below-elbow plaster cast immobilisation (36). These 71 patients represent the majority of a randomised series of 88 patients whose short-term outcome has previously been reported. Those patients available for later review were similar in age, gender and hand dominance.

There was no statistical difference in symptoms and disability as assessed by the mean Patient Evaluation Measure (p = 0.4), or mean Patient-Rated Wrist Evaluation (p = 0.9), the mean range of movement of the wrist (p = 0.4), mean grip strength (p = 0.8), or mean pinch strength (p = 0.4).

Radiographs were available from the final review for 59 patients. Osteoarthritic changes were seen in the scaphotrapezial and radioscaphoid joints in eight (13.5%) and six patients (10.2%), respectively. Three patients had asymptomatic lucency surrounding the screw. One non-operatively treated patient developed nonunion with avascular necrosis. In five patients who were treated non-operatively (16%) there was an abnormal scapholunate angle ( > 60°), but in four of these patients this finding was asymptomatic.

No medium-term difference in function or radiological outcome was identified between the two treatment groups.

Hand function was evaluated in 105 patients who had been operated on in early infancy for brachial plexus birth palsy. The mean follow-up after surgery was for 13.4 years (5.0 to 31.5). Fine sensation, stereognosis, grip and pinch strength and the Raimondi scale were recorded.

Fine sensation was normal in 34 of 49 patients (69%) with C5–6 injury, 15 of 31 (48%) with C5–7 and in 8 of 25 (32%) with total injury. Loss of protective sensation or absent sensation was noted in some palmar areas of the hand in 12 of 105 patients (11%). Normal stereognosis was recorded in 88 of the 105 patients (84%), whereas only 9 of the 105 (9%) had normal grip strength. The mean Raimondi scale scores were 4.57 (3 to 5) (C5–6), 4.26 (1 to 5) (C5–7) and 2.16 (0 to 5) in patients with total injury.

The location of impaired sensation was related to the distribution of the root injury. Avulsion type of injury correlated with poor recovery of hand function.

Locognosia, the ability to localise touch, is one aspect of tactile spatial discrimination which relies on the integrity of peripheral end-organs as well as the somatosensory representation of the surface of the body in the brain. The test presented here is a standardised assessment which uses a protocol for testing locognosia in the zones of the hand supplied by the median and/or ulnar nerves.

The test-retest reliability and discriminant validity were investigated in 39 patients with injuries to the median or ulnar nerve. Intraclass correlation coefficients were used to calculate the test-retest reliability. Discriminant validity was assessed by comparing the injured with the unaffected hand.

Excellent test-retest reliability was demonstrated for the injuries to the median (intraclass correlation coefficient 0.924, 95% confidence interval 0.848 to 1.00) and the ulnar nerves (intraclass correlation coefficient 0.859, 95% confidence interval 0.693 to 1.00). The magnitude of the difference in scores between affected and unaffected hands showed good discriminant validity. For injuries to the median nerve the mean difference was 11.1 points (1 to 33; sd 7.4), which was statistically significant (p < 0.0001, paired t-test) and for those of the ulnar nerve it was 4.75 points (1 to 13.5; sd 3.16), which was also statistically significant (paired t-test, p < 0.0001).

The locognosia test has excellent test-retest reliability, is a valid test of tactile spatial discrimination and should be included in the evaluation of outcome after injury to peripheral nerves.

We developed a questionnaire to assess patient-reported outcome after surgery of the elbow from interviews with patients. Initially, 17 possible items with five response options were included. A prospective study of 104 patients (107 elbow operations) was carried out to analyse the underlying factor structure, dimensionality, internal and test-retest reliability, construct validity and responsiveness of the questionnaire items. This was compared with the Mayo Elbow performance score clinical scale, the Disabilities of the Arm, Shoulder and Hand questionnaire, and the Short-Form (SF-36) General Health Survey. In total, five questions were considered inappropriate, which resulted in the final 12-item questionnaire, which has been referred to as the Oxford elbow score. This comprises three unidimensional domains, ‘elbow function’, ‘pain’ and ‘social-psychological’; with each domain comprising four items with good measurement properties.

This new 12-item Oxford elbow score is a valid measure of the outcome of surgery of the elbow.

In a prospective randomised trial of calcifying tendinitis of the rotator cuff, we compared the efficacy of dual treatment sessions delivering 2500 extracorporeal shock waves at either high- or low-energy, via an electromagnetic generator under fluoroscopic guidance. Patients were eligible for the study if they had more than a three-month history of calcifying tendinitis of the rotator cuff, with calcification measuring 10 mm or more in maximum dimension. The primary outcome measure was the change in the Constant and Murley Score.

A total of 80 patients were enrolled (40 in each group), and were re-evaluated at a mean of 110 (41 to 255) days after treatment when the increase in Constant and Murley score was significantly greater (t-test, p = 0.026) in the high-energy treatment group than in the low-energy group. The improvement from the baseline level was significant in the high-energy group, with a mean gain of 12.5 (−20.7 to 47.5) points (p < 0.0001). The improvement was not significant in the low-energy group. Total or subtotal resorption of the calcification occurred in six patients (15%) in the high-energy group and in two patients (5%) in the low-energy group.

High-energy shock-wave therapy significantly improves symptoms in refractory calcifying tendinitis of the shoulder after three months of follow-up, but the calcific deposit remains unchanged in size in the majority of patients.

Our aim was to determine the clinical value of MRI and CT arthrography in predicting the presence of loose bodies in the elbow.

A series of 26 patients with mechanical symptoms in the elbow had plain radiography, MRI and CT arthrography, followed by routine arthroscopy of the elbow. The location and number of loose bodies determined by MRI and CT arthrography were recorded. Pre-operative plain radiography, MRI and CT arthrography were compared with arthroscopy.

Both MRI and CT arthrography had excellent sensitivity (92% to 100%) but low to moderate specificity (15% to 77%) in identifying posteriorly-based loose bodies. Neither MRI nor CT arthrography was consistently sensitive (46% to 91%) or specific (13% to 73%) in predicting the presence or absence of loose bodies anteriorly. The overall sensitivity for the detection of loose bodies in either compartment was 88% to 100% and the specificity 20% to 70%. Pre-operative radiography had a similar sensitivity and specificity of 84% and 71%, respectively.

Our results suggest that neither CT arthrography nor MRI is reliable or accurate enough to be any more effective than plain radiography alone in patients presenting with mechanical symptoms in the elbow.

The purpose of this study was to assess the long-term results (more than ten years) of two types of cemented ulnar component with type-5 Kudo total elbow arthroplasty in a consecutive series of 56 patients (60 elbows) with rheumatoid arthritis, and to compare the results in elbows above and below a Larsen grade IV.

There was no radiolucency around the humeral component. Patients in whom a metal-backed ulnar component and a porous-coated stem were used had better clinical results and significantly less progression of radiolucent line formation around the ulnar component. They also had a significantly better long-term survival than patients with an all-polyethylene ulnar component. The clinical results of arthroplasty using all-polyethylene ulnar components were inferior, regardless of the degree of joint destruction.

We conclude that the type-5 Kudo total elbow arthroplasty with cementless fixation of the porous-coated humeral component and cemented fixation of a metal-backed ulnar component is acceptable and well-tolerated by rheumatoid patients.

In a prospective, randomised study on the repair of tears of the rotator cuff we compared the clinical results of two suture techniques for which different suture materials were used.

We prospectively randomised 100 patients with tears of the rotator cuff into two groups. Group 1 had transosseous repair with No. 3 Ethibond using modified Mason-Allen sutures and group 2 had transosseous repair with 1.0 mm polydioxanone cord using modified Kessler sutures. After 24 to 30 months the patients were evaluated clinically using the Constant score and by ultrasonography.

Of the 100 patients, 92 completed the study. No significant statistical difference was seen between the two groups: Constant score, 91% vs 92%; rate of further tear, 18% vs 22%; and revision, 4% vs 4%. In cases of further tear the outcome in group 2 did not differ from that for the intact repairs (91% vs 91%), but in group 1 it was significantly worse (94% vs 77%, p = 0.005).

Overall, seven patients had complications which required revision surgery, in four for pain (two in each group) and in three for infection (two in group 1 and one in group 2).

Ulnar nerve function, during and after open reduction and internal fixation of fractures of the distal humerus with subperiosteal elevation of the nerve, was assessed by intra-operative neurophysiological monitoring. Intermittent recording of the compound muscle action potentials was taken from the hypothenar muscles in 18 neurologically asymptomatic patients.

The mean amplitude of the compound muscle action potential after surgery was 98.1% (sd 17.6; −37% to +25%). The amplitude improved in six patients following surgery. Despite unremarkable recordings one patient had progressive paresis. Motor impairment is unlikely if the compound muscle action potential is continuously preserved and not reduced by more than 40% at the end of surgery. Temporary decreases in amplitude by up to 70% were tolerated without clinical consequences. However, repeated clinical examination is obligatory to recognise and treat early post-operative palsy.