Olecranon plates used for the internal fixation of complex olecranon fractures are applied directly over the triceps tendon on the posterior aspect of the olecranon. The aim of the study is to describe the relationship of the plates and screws to the triceps tendon at the level of the olecranon. Eight cadaveric elbows were used. Dimensions of the triceps tendon at the insertion and 1cm proximal were measured. A long or a short olecranon plate was then applied over the olecranon and the most proximal screw applied. The length of the plate impinging on the tendon and the level of the screw tract on the tendon and bone were measured. The mean olecranon height was 24.3cm (22.4-26.9cm) with a tip-to-tendon distance of 14.5cm (11.9-16.2cm). The triceps tendon footprint averaged 13.3cm (11.7-14.9cm) and 8.8cm (7.6-10.2cm) in width and length, respectively. The mean width of the central tendon 1 cm proximal to the footprint was 6.8 cm. The long olecranon plate overlay over more movable tendon length than did the short plate and consequently the superior screw pierced the triceps tendon more proximally with the long plate. Using the Mann-Whitney U test, the differences were significant. The long olecranon plates encroach on more triceps tendon than short plates. This may be an important consideration for olecranon fractures with regards implant loosening or triceps tendon injury

Introduction. Distal triceps tendon rupture is related to high complication rates with up to 25% failures. Elbow stiffness is another severe complication, as the traditional approach considers prolonged immobilization to ensure tendon healing. Recently a dynamic high-strength suture tape was designed, implementing a silicone-infused core for braid shortening and preventing repair elongation during mobilization, thus maintaining constant tissue approximation. The aim of this study was to biomechanically compare the novel dynamic tape versus a conventional high-strength suture tape in a human cadaveric distal triceps tendon rupture repair model. Method. Sixteen paired arms from eight donors were used. Distal triceps tendon rupture tenotomies and repairs were performed via the crossed transosseous locking Krackow stitch technique for anatomic footprint repair using either conventional suture tape (ST) or novel dynamic tape (DT). A postoperative protocol mimicking intense early rehabilitation was simulated, by a 9-day, 300-cycle daily mobilization under 120N pulling force followed by a final destructive test. Result. Significant differences were identified between the groups regarding the temporal progression of the displacement in the distal, intermediate, and proximal tendon aspects, p<0.001. DT demonstrated significantly less displacement compared to ST (4.6±1.2mm versus 7.8±2.1mm) and higher load to failure (637±113N versus 341±230N), p≤0.037. DT retracted 0.95±1.95mm after each 24-hour rest period and withstood the whole cyclic loading sequence without failure. In contrast, ST failed early in three specimens. Conclusion. From a biomechanical perspective, DT revealed lower tendon displacement and greater resistance in load to failure over ST during simulated daily mobilization, suggesting its potential for earlier elbow mobilization and prevention of postoperative elbow stiffness

Nerve transfer is an emerging treatment to restore upper limb function in people with tetraplegia. The objective of this study is to examine if a flexible collage sheet (FCS) can act as epineurial-like substitute to promote nerve repair in nerve transfer. A preclinical study using FCS was conducted in a rat model of sciatic nerve transection. A prospective case series study of nerve transfer was conducted in patients with C5-C8 tetraplegia who received nerve transfer to restore upper limb function. Motor function in the upper limb was assessed pre-treatment, and at 6-,12-, and 24-months post-treatment. Macroscopic assessment in preclinical model showed nerve healing by FCS without encapsulation or adhesions. Microscopic examination revealed that a new, vascularised epineurium-like layer was observed at the FCS treatment sites, with no evidence of inflammatory reaction or nerve compression. Treatment with FCS resulted in well-organised nerve fibres with dense neurofilaments distal to the coaptation site. Axon counts performed proximal and distal to the coaptation site showed that 97% of proximal axon count of myelinated axons regenerated across the coaptation site after treatment with CND. In the proof of concept clinical study 17 nerve transfers were performed in five patients. Nerve transfers included procedures to restore triceps function (N=4), wrist/finger/thumb extension (N=6) and finger flexion (N=7). Functional motor recovery (MRC ≥3) was achieved in 76% and 88% of transfers at 12 and 24 months, respectively. The preclinical study showed that FCS mimics epineurium and enable to repair nerve resembled to normal nerve tissue. Clinical study showed that patients received nerve transfer with FCS experienced consistent and early return of motor function in target muscles. These results provide proof of concept evidence that CND functions as an epineurial substitute and is promising for use in nerve transfer surgery

We describe a lateral approach to the distal humerus based on initial location of the superficial branches of the radial nerve, the inferior lateral cutaneous nerve of the arm and the posterior cutaneous nerve of the forearm. In 18 upper limbs the superficial branches of the radial nerve were located in the subcutaneous tissue between the triceps and brachioradialis muscles and dissected proximally to their origin from the radial nerve, exposing the shaft of the humerus. The inferior lateral cutaneous nerve of the arm arose from the radial nerve at the lower part of the spiral groove, at a mean of 14.2 cm proximal to the lateral epicondyle. The posterior cutaneous nerve of the forearm arose from the inferior lateral cutaneous nerve at a mean of 6.9 cm (6.0 to 8.1) proximal to the lateral epicondyle and descended vertically along the dorsal aspect of the forearm. The size and constant site of emergence between the triceps and brachioradialis muscles constitute a readily identifiable landmark to explore the radial nerve and expose the humeral shaft

Current knowledge regarding upper limb myotomes is based on historic papers. Recent advances in magnetic resonance imaging (MRI) and surgical exploration with intraoperative nerve stimulation now allow accurate identification of nerve root injuries in the brachial plexus. The aim of this study is to identify the myotome values of the upper limb associated with defined supraclvicular brachial plexus injuries. 57 patients with partial supraclavicular brachial plexus injuries were identified from the Scottish brachial plexus database. The average age was 28 years and most injuries secondary to motor cycle accidents or stabbings. The operative and MRI findings for each patient were checked to establish the root injuries and the muscle powers of the upper limb documented. The main patterns of injuries identified involved (C5,6), (C5,6,7), (C5,6,7,8) and (C8, T1). C5, 6 injuries were associated with loss of shoulder abduction, external rotation and elbow flexion. In 30% of the 16 cases showed some biceps action from the C7 root. C5,6,7 injuries showed a similar pattern of weakness with the additional loss of flexor carpi radialis and weakness but not total paralysis of triceps in 85% of cases. C5,6,7,8 injuries were characterised by loss of pectoralis major, lattisimus dorsi, triceps, wrist extension, finger extension and as well as weakness of the ulnar intrinsic muscles. We identified weakness of the flexor digitorum profundus to the ulnar sided digits in 83% of cases. T1 has a major input to innervation of flexors of the radial digits and thumb, as well as intrinsics. This is the largest study of myotome values in patients with surgically or radiologically confirmed injuries in the literature and presents information for general orthopaedic surgeons dealing with trauma patients for the differentiation of different patterns of brachial plexus injuries. In addition we have identified new anatomical relationships not previously described in upper limb myotomes

Introduction. The healing of Achilles tendon rupture is slow and jogging is usually allowed already 6 months after injury. However, the metabolic status of the healing tendon is largely unknown at the time-points when increased loading is allowed. The purpose of this study was to investigate tendon metabolic response and blood flow at 3, 6 and 12 months after Achilles tendon rupture by positron emission tomography (PET) and ultrasound-Power Doppler (UPD). Materials and Methods. 23 patients that had surgical repair of a total Achilles tendon rupture (3 (n=7), 6 (n=7) or 12 (n=9) months earlier) participated in the study. The triceps surae complex was loaded during 20 min of slow treadmill walking. A radioactive tracer (FDG) was administered during this walking and glucose uptake was measured bilaterally by the use of PET. Blood flow was recorded by UPD and patient reported outcome scored by Achilles tendon rupture score (ATRS) and VISA-A. Non-parametric statistics were used for statistical analysis. Results. Metabolic activity was higher in the healing tendon compared to intact tendon at all time-points, however the activity decreased over time (510%, 260% and 62% higher on the healing side compared to the intact side at 3, 6 and 12 months respectively, p<0.001). The metabolic activity was higher in the core than the periphery of the healing tendon, at 3 and 6 months (p<0.02), but lower at 12 months (p=0.06). Interestingly, metabolic activity was negatively related to ATRS, 6 months after rupture (r=−0.89, p<0.01). UPD was also 100-fold and 61-fold higher respectively in the healing than the intact healthy tendon at 3 months (p<0.05) and 6 months (p=0.06), but not at 12 months. Discussion. These results demonstrate that the healing process measured by metabolic and blood flow activity still remains high 6 months after rupture when increased loading is allowed. In fact, PET determined metabolic activity remained elevated up to a year after injury when measures of hyper-vascularization were normalized. Although speculative, the strong negative correlation between tendon metabolism and patient reported outcome indicates that a high metabolic activity 6 months after the injury may be related to poor healing outcome

Using an osteotomy of the olecranon as a model of a transverse fracture in 22 cadaver elbows we determined the ability of three different types of suture and stainless steel wire to maintain reduction when using a tension-band technique to stabilise the bone. Physiological cyclical loading simulating passive elbow movement (15 N) and using the arms to push up from a chair (450 N) were applied using an Instron materials testing machine whilst monitoring the osteotomy site with a video extensometer. Each osteotomy was repaired by one of four materials, namely, Stainless Steel Wire (7), No 2 Ethibond (3), No 5 Ethibond (5), or No 2 FiberWire (7).

There were no failures (movement of > 2 mm) with stainless steel wire or FiberWire and no significant difference in the movements measured across the site of the osteotomy (p = 0.99). The No. 2 Ethibond failed at 450 N and two of the five of No. 5 Ethibond sutures had a separation of > 2 mm at 450 N.

FiberWire as the tension band in this model held the reduction as effectively as stainless steel wire and may reduce the incidence of discomfort from the hardware. On the basis of our findings we suggest that a clinical trial should be undertaken

We have investigated the anatomy of the proximal part of the ulna to assess its influence on the use of plates in the management of fractures at this site. We examined 54 specimens from cadavers. The mean varus angulation in the proximal third was 17.5° (11° to 23°) and the mean anterior deviation 4.5° (1° to 14°). These variations must be considered when applying plates to the dorsal surface of the ulna for Monteggia-type fractures. A pre-operative radiograph of the contralateral elbow may also be of value.

The effect of zoledronic acid on bone ingrowth was examined in an animal model in which porous tantalum implants were placed bilaterally within the ulnae of seven dogs. Zoledronic acid in saline was administered via a single post-operative intravenous injection at a dose of 0.1 mg/kg. The ulnae were harvested six weeks after surgery. Undecalcified transverse histological sections of the implant-bone interfaces were imaged with backscattered scanning electron microscopy and the percentage of available pore space that was filled with new bone was calculated. The mean extent of bone ingrowth was 6.6% for the control implants and 12.2% for the zoledronic acid-treated implants, an absolute difference of 5.6% (95% confidence interval, 1.2 to 10.1) and a relative difference of 85% which was statistically significant. Individual islands of new bone formation within the implant pores were similar in number in both groups but were 69% larger in the zoledronic acid-treated group. The bisphosphonate zoledronic acid should be further investigated for use in accelerating or enhancing the biological fixation of implants to bone.

We studied the effect of vitamin C on fracture healing in the elderly. A total of 80 elderly Osteogenic Disorder Shionogi rats were divided into four groups with different rates of vitamin C intake. A closed bilateral fracture was made in the middle third of the femur of each rat. Five weeks after fracture the femora were analysed by mechanical and histological testing. The groups with the lower vitamin C intake demonstrated a lower mechanical resistance of the healing callus and a lower histological grade. The vitamin C levels in blood during healing correlated with the torque resistance of the callus formed (r = 0.525). Therefore, the supplementary vitamin C improved the mechanical resistance of the fracture callus in elderly rats. If these results are similar in humans, vitamin C supplementation should be recommended during fracture healing in the elderly.

Strains applied to bone can stimulate its development and adaptation. High strains and rates of strain are thought to be osteogenic, but the specific dose response relationship is not known. In vivo human strain measurements have been performed in the tibia to try to identify optimal bone strengthening exercises for this bone, but no measurements have been performed in the distal radial metaphysis, the most frequent site of osteoporotic fractures. Using a strain gauged bone staple, in vivo dorsal metaphyseal radial strains and rates of strain were measured in ten female patients during activities of daily living, standard exercises and falls on extended hands. Push-ups and falling resulted in the largest compression strains (median 1345 to 3146 με, equivalent to a 0.1345% to 0.3146% length change) and falling exercises in the largest strain rates (18 582 to 45 954 με/s). On the basis of their high strain and/or strain rates these or variations of these exercises may be appropriate for distal radial metaphyseal bone strengthening.