Case report illustrating use of serial elastic tension digital neoprene orthoses (ETDNO) protocol in the treatment of proximal interphalangeal joint flexion contracture

INTRODUCTION

This case report details the application of a treatment regimen using a serial elastic tension digital neoprene orthosis (ETDNO) protocol for a patient with an eight-month-old finger crush injury who experienced recurrence of a 45º proximal interphalangeal joint (PIPJ) flexion contracture two months after arthrolysis.

PURPOSE OF THE STUDY

To illustrate how the application strategy of ETDNO can increase the daily total end range time (TERT) and modify finger stiffness.

RESULTS

The patient reached full extension following 15 weeks of ETDNO treatment. The six-month follow-up evaluation revealed that the PIPJ was stable with full flexion and extension. The joint did not require continued orthosis use.

DISCUSSION

The literature describes orthosis application as the treatment of choice for PIPJ flexion contracture, but no study has described an ideal program for use nor the full and stable resolution of the flexion contracture. The current literature describes a maximum daily total end range time (TERT) of 12 hours a per day. The serial ETDNO protocol that this study described increased the daily TERT to nearly 24 hour per day and demonstrated an excellent result in the treatment of PIPJ flexion contracture CONCLUSION: This outcome suggests that clinicians will want to consider this new orthosis design and management protocol as a novel option for the treatment of PIPJ flexion contracture. We need future research to better define the optimum number of hours of daily TERT for the effective treatment of PIPJ flexion contracture. In addition, we will also benefit from the exploration of the optimum orthosis design to enable the highest amount of TERT.

A Cadaver Based Comparison of Two Elastic Tension Proximal Interphalangeal Joint (PIPJ) Extension Orthoses with Focus on Force Generation and Pressure Distribution

Proximal interphalangeal joint flexion contracture is a frequent condition in hand therapy. Clinicians most frequently apply orthosis management for conservative treatment. Orthoses should apply forces for long periods of time following the total end range time (TERT) concept. These forces necessarily transmit through the skin; however, skin has physiological limitations determined by blood flow. Using three fresh frozen human cadavers, this study quantified and compared forces, skin contact surfaces and pressure of two finger orthoses, an elastic tension digital neoprene orthosis (ETDNO) and an LMB 501 orthosis. The study also investigated the effects of a new method of orthosis construction (serial ETDNO orthoses) that customizes forces to a specific finger position. We evaluated forces and contact surfaces for multiple ETDNO models tailored to the cadaver fingers in multiple PIP flexion positions. The results showed that the LMB 501 orthosis applied pressures beyond the recommended limits if applied for more than eight hours a day. This fact was the cause of time limited LMB orthosis application. This results also show that, at 30° of PIPJ flexion, straight ETDNOs created a mean pressure approaching the end of the recommended pressure limits. If the therapist modified the ETDNO design, the skin pressure decreased and reduced the risk of skin damage. With the results of this study, we concluded that for PIPJ flexion contracture, the upper limit of force application is 200 g (1.96 N). Forces beyond this amount would likely cause skin irritation and possibly skin injuries. This would cause a reduction in the daily TERT and limit outcomes.

A Comparison between Two Intervals of Daily Total End Range Time for Treatment of Proximal Interphalangeal Joint Flexion Contracture Using an Elastic Tension Digital Neoprene Orthosis

Focusing on fingers with proximal interphalangeal joint flexion contractures, this study seeks to determine whether significant differences exist between the joint passive range of motion PROM improvement when receiving higher doses of daily total end range time (TERT) compared to those that receive lower doses. The study randomized a parallel group of fifty-seven fingers in fifty patients with concealed allocation and assessor blinding. Divided into two groups receiving different doses of daily total end range time with an elastic tension digital neoprene orthosis, they also participated in an identical exercise program. Patients reported orthosis wear time, and the researchers performed goniometric measurements at every session during the three-week period. The primary outcome related the time patients wore the orthosis to the degrees of improvement in PROM extension. Compared to group B (daily TERT of twelve hours), group A (TERT, twenty+ hours) showed a statistically significant greater improvement in PROM after three weeks of treatment. Group A improved by a mean of 29° compared to group B's mean of 19° improvement. This study provides evidence that a higher dose of daily TERT can generate better results in the treatment of the proximal interphalangeal joint flexion contractures.

Preliminary study of elastic-tension digital neoprene orthoses for proximal interphalangeal joint flexion contracture

Flexion contracture of the proximal interphalangeal joint (PIPJ) is one of the most frequent complications in finger trauma. Orthoses are the most widely used method to optimize total end-range time (TERT). No previous studies showed that an elastic tension orthosis could be applied for longer than 12 h. We aimed to demonstrate that the elastic-tension digital neoprene orthosis (ETDNO) can achieve higher TERT and therefore better range of motion than other elastic-tension orthoses (ETO) described in the literature. A prospective study of treatment of PIPJ flexion contracture included 10 PIP joints in 8 patients who met the selection criteria. They were instructed to use the ETDNO for around 23 h per day as far as possible, during a period of 3 weeks. Patients reported a mean TERT of 20.6 h a day. PIPJ contracture improved by a mean Torque Range of Motion (TROM) of 23.5° at 500 g and 22.9° at 800 g of passive extension force during the 3-week treatment. Based on the results of this study, the ETDNO appears to offer a highly effective approach for improving PIPJ flexion contracture, increasing range of motion in extension. ETDNO's efficacy probably lies in the significantly improved comfort and low-profile design, enabling excellent compliance and thus optimizing TERT. LEVEL OF EVIDENCE: Level III.

Functional patterns of thumb key pinch and their influence on thumb strength and stability

Introduction

Trapeziometacarpal osteoarthritis (TMC OA) is a common condition frequently related to instability and hypermobility. Many factors are involved in the development of this degenerative process. Recent research suggests that the position of the metacarpophalangeal (MCP) joint may influence TMC joint contact wear patterns and subsequent development of OA. The aim of this study is to explore the alignment of the MCP joint of the thumb during lateral pinch in order to describe the naturally occurring alignment in a group of healthy volunteers without symptoms.

Methods

One hundred and nine participants were asked to apply a lateral pinch manoeuvre to a pinchmeter, while their thumbs were assessed. Passive hypermobility of the thumb MCP (MCP) joint was assessed, key pinch strength was measured, key pinch position was photographed and the angle of the joints during the assessment was measured.

Results

Four different functional pinch patterns were identified. The most frequent pattern seems to be MCP hyperextension described by Moulton as harmful for the TMC joint. The level of strength obtained did not correspond to the pinch pattern used, and hypermobility of the thumb MCP joint did not determine the position of the thumb during key pinch.

Conclusion

Four different thumb postures were identified during lateral pinch; however, these postures were not associated with any difference in pinch strength. We conclude that the more unstable and mechanically inefficient postures are compensated by functional capacity.

[Tension force in dynamic splints made of neoprene]

Dynamic splints are the most difficult ortheses to make. Unrestricted finger joint mobility is usually prevented by the size of their components. Ortheses made out of neoprene material have the advantage of being pliable and at the same time can be constructed as dynamic splints. Neoprene material elasticity allows conforming it into a tube that can be fitted over a finger, spreading uniform pressure. A traction slip can be cemented to the neoprene finger tube. With neoprene splints, lever arms are more efficient. Their tubular design applies and spreads traction and countertraction forces in all directions. Neoprene material's elasticity contributes in reducing edema formation as well as distributes forces applied to the finger over a large area. The risk of excessive pressure is the only drawback of an elastic tubular design, it may cause pain and tissue ischemia. A meticulous tailoring prevents this potential risk.