Optimization of Surgical Outcome in Lower-Extremity Nerve Decompression Surgery

SLR - May 2018 - Andrew Yang

Reference: Rinkel WD, de Kleijn JL, MacarĂ© van Maurik JFM, Coert JH. Optimization of Surgical Outcome in Lower-Extremity Nerve Decompression Surgery. Plast Reconstr Surg. 2018 Feb;141(2):482–496.

Scientific Literature Review

Reviewed By: Andrew Yang, DPM
Residency Program: Highlands/Presbyterian Saint Luke’s, Denver, CO

Podiatric Relevance: Peripheral neuropathy caused by diabetes mellitus is a common pathology seen in the practice of a podiatric physician. Peripheral neuropathy causes symptoms, such as pain, tingling, burning and loss of sensation, that reduce the quality of life of patients and predispose patients to foot ulcers and consequently, amputations. When faced with such patients in the clinic, there are not many options to help alleviate the symptoms of neuropathy. It has been debated whether nerve decompression helps alleviate the symptoms of peripheral neuropathy, but this study aims to investigate which factors are associated with a favorable surgical outcome.

Methods: The authors did a five-year follow-up study of patients who participated in the Lower-Extremity Nerve entrapment study (LENS). The study consisted of 42 patients living with diabetes who complained of painful neuropathy and showed bilateral compression neuropathies of the common peroneal nerve, superficial peroneal nerve, deep peroneal nerve and tibial nerve at the tarsal tunnel. These patients were randomized to either lower-extremity nerve decompression surgery or control group. VAS, SF-36 and EQ-5D was used as outcome measurements. Sensory status was assessed by the 1/2-point discrimination test. Differences between unilateral versus bilateral decompressions were investigated.

Results: Of the 42 patients who participated in the LENS study, 31 were available for follow-up with a mean age of 66.2 and mean time of 4.6 years. Of the 31 patients, 23 of the patients were unilateral surgeries and eight were bilateral. Compared to those who underwent unilateral operations, patients who underwent bilateral operations were significantly younger when diagnosed with DM (mean 33.9 vs. 50.2 years). There was a trend toward lower BMI, lower triglyceride levels, higher quality of life and higher percentage of intact 1/2-point discrimination in patients with bilateral surgery.

At 12 months, there was a statistically significant difference in VAS pain scores between bilateral and unilateral operated patients (mean 1.8 vs. 4.3). After five years, there was no significant difference in VAS pain scores between the two groups or compared to baseline. SF-36 score at the five-year mark showed higher scores in all domains in the bilateral group compared to the unilateral group, except for physical functioning. At the five-year follow-up, the EQ-5D and VAS scores were significantly higher in the bilateral compared to unilateral group. A questionnaire at the five-year mark showed significant differences between decompressed and nondecompressed legs, regarding improvement in sensation (35.5 percent vs. 9.7 percent) and decrease in pain (35.5 percent vs. 12.9 percent). There was a higher amount of permanent improvement in pain in the bilateral group vs. the unilateral group (50 percent vs. 13 percent). Permanent worsening of pain was significantly higher in contralateral leg of unilateral operated patients. Sensory tests did not show changes with 1/2-point discrimination tests at the five-year follow-up between each group or in comparison to preoperative evaluation.

Conclusions: The study suggests that the beneficial effects of lower-extremity nerve decompression surgery may be achieved in patients with mild to moderate complaints of compression neuropathy, shorter duration of DM, lower age, metabolic control and without profound sensory loss.