Outcomes in lower limb amputation following trauma: a systematic review and meta-analysis

Lower limb amputation (LLA) is life-changing surgery. Shorter residual limbs are known to place greater physiological strain on patients than longer residual limbs; however, there is ongoing debate as to whether through-knee amputations are preferable to above-knee amputations. This analysis aims to resolve this question by systematically collecting and pooling published and unpublished data on this subject.

An exhaustive search of Medline, Embase and Recal databases was made for outcome studies of patients with lower limb amputations following trauma. Studies concerned with amputations of the upper limb or foot and ankle were excluded as were papers reporting outcomes in a population of mixed trauma and non-trauma patients. Authors of studies published in the last 10 years were contacted for unpublished details. Patients were then divided, according to amputation height, into four groups: below-knee amputation (BKA), through-knee amputation (TKA), above-knee amputation (AKA) and bilateral amputation. The primary outcome measure was Physical Component Score (PCS) of the short-form-36 measure of quality of life and secondary outcomes were pain, employment, ability to walk 500m and proportion of time that prosthesis is worn.

As many as 27 studies were included, representing a total of 3105 patients, 1855 with a BKA, 104 with a TKA, 888 with an AKA and 258 bilateral amputees. There was progressive and significant lowering of PCS (worsening outcomes) as unilateral amputation height became more proximal from BKA to TKA and AKA. A significantly greater proportion of patients with a BKA or a TKA were able to walk 500m than those with an AKA or bilateral amputation (p=0.0035). However, patients with a TKA wore their prosthesis significantly less, and had significantly more pain than those with an AKA.

This study describes the impact of LLA of different levels on patients' lives. The results indicate that patients with a TKA have a better physical quality of life than those with an AKA and, therefore, support the surgical strategy of maintaining maximum length and performing TKA in preference to AKA, where possible.