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.
Waitemata District Health Board (WDHB) is contracted through public funding to achieve approximately 500 total hip arthroplasties per year. A pilot was established to increase productivity and reduce costs in these surgical procedures. Current barriers to efficiency in elective surgery are slow patient turnover, increase in costs of consumables and staff employment issues. This pilot introduced: A change in drivers and incentives so remuneration and rewards were related to productivity (replaced medical salaries), an alliance contracting concept (1), encouraged productivity, contained costs (consumables) increase surgeon and anaesthetist involvement in overall patient care (reduce need for additional medical staff), reduced length of hospital stay, shortened patient journey, established surgeon/anaesthetist/nurse team. Inclusion criteria:1. Hip replacements in DRG103C: Hip replacement W/O catastrophic or severe CC. 2. ASA grade <4. 3. Cases July to November 2010 Comparison of baseline data was then carried out between this pilot and compared with data from the main campus (both sites had dedicated elective operating lists). Theatre time was reduced from 167.5 to 97 minutes (42%), length of stay 5.58 days to 3.46 days (38%), OR costs $3830 to $2708 (29%). There was an increase in medical costs but a 12% saving was achieved overall. The pilot has shown that it is possible to significantly reduce costs in elective surgery through an increase in productivity. To reduce costs of elective surgery, the culture/environment needs to change to encourage the individual surgeons, anaesthetists, and other members of the team to increase productivity and decrease costs.
Waitemata DHB serves a population of approximately 500,000. There are 396 general practitioners who refer to the services. Approximately 400 patients are referred per month. Budget constraints mean not all patients referred can be seen and various Ministry of Health guidelines and Health and Disability Commission rulings help to determine which patients will be seen. All referrals to the service are assessed by one surgeon. There are specific requirements for referral of patients with certain complaints. Assistance is given to the general practitioner in organising the more specialist investigations. Help is given to GPs by telephone for patient management particularly of the simpler conditions. Approximately a quarter of patients referred are referred back to the GP. MRI and CT scans are arranged of which half are returned. Time must be allocated within the department to allow this specialist liaison with GPs to occur.
The goal of this study was to determine which of two techniques for the treatment of peri-prosthetic femoral shaft fractures has the greatest torsional integrity. The study designed was a laboratory study, using 13 matched pairs of embalmed femurs. The femurs were implanted with a cemented total hip prosthesis, with a transverse osteotomy distal to the stem. These fractures were fixed either with a metal plate with three proximal unicortical screws and three distal bicortical screws or with three proximal cables and three distal bicortical screws. The fracture fixation was tested to failure in torsion. The pattern of failure and torsional limits were recorded. There was no significant difference to failure level between the two constructs. Failure with the proximal unicortical screws was usually catastrophic versus non-catastrophic with proximal cables. The femurs were significantly more likely to fracture in internal rotation. Treatment with proximal cables has the same load to failure in torsion but significantly less complications than with unicortical screws, in agreement with the literature. The findings of the construct being weaker in internal rotation, appears to be a new finding and an area of possible new research.
The human hip capsule is a heterogeneous structure contributing greatly to the stability of this joint. A posterior approach to the hip necessarily sacrifices the ischio-femoral ligament but the decision to release the ilio-femoral and pubo-femoral ligaments remains at the discretion of the surgeon. This mechanical study aims to demonstrate that these anterior capsular structures, when left intact, may limit the external rotational range of motion when the variables of femoral offset, leg length and neck version are adjusted at the time of surgery. A dry bone pelvis-femur model was prepared and registered with the Stryker iNstride Hip Navigation software. A cemented 28 HDPE contemporary cup was inserted at 45° inclination with 20° of anteversion and a revision modular stem implanted in the femoral medullary canal. Artificial ilio-femoral and pubo-femoral ligaments were then prepared from plastinated rubber fabric and mounted in their anatomical positions. Using this model, a range of restoration body sizes was sequentially introduced to vary the offset. The rotational range of motion was then assessed. Repeat measurements were made using + 10mm length bodies across the same offset range. Finally, assessments of rotational range of motion were made using the 19mm body alone while varying neck lengths and degrees of version were trialled. All measurements of external rotation were taken in a position of 0° hip flexion and 0° abduction, as determined using the Stryker iNstride Hip Navigation System. As femoral offset was increased using our model, there was a progressive loss of external rotation. This consistent restriction of external rotation was further accentuated when +10mm length bodies were trialled across the same range of offsets. When a standard 19mm restoration body was placed and a range of heads trialled, it was again found that increasing neck length consistently correlated with a reduction in external rotation. Varying the restoration neck version with a standard head, it was found that increasing retroversion correlated with an increase in the external rotational range of motion. The findings of this mechanical study suggest a progressive limitation of hip external rotation with increasing femoral offset and leg length when the anterior capsular structures are intact. Such findings are of importance in pre-operative planning as they suggest that increases in these variables may significantly limit a patient’s range of external rotation unless the anterior hip capsule is released. Such considerations must of course be balanced against the potential to destabilise the hip if too extensive a soft tissue release is performed. The artificial model used in this study is intended to approximate the human hip and its ligaments. The absolute values for rotational range of motion measured using the Stryker hip navigation system are less significant than the overall trend which they suggest. A patient-based study is now planned to further test these findings.
