Gordon J Eric, Davis Lauren E
Department of Orthopaedic Surgery, Washington University School of Medicine.
St. Louis Children's Hospital.
J Pediatr Orthop. 2019 Jul;39(Issue 6, Supplement 1 Suppl 1):S10-S13. doi: 10.1097/BPO.0000000000001396.
The long-term effects of small limb length discrepancies have been poorly documented in the literature. References to low back pain, hip pathology, knee pathology, and foot problems abound in the popular literature. Health care providers frequently recommend the use of lifts for structural and functional limb length discrepancies, yet the natural history of limb length inequality as well as the effectiveness of treatments that may be recommended are obscure. The purpose of this paper is to document and evaluate the literature associated with small limb length discrepancies.
A search of the English literature was carried out using PubMed to identify papers dealing with the effects of limb length discrepancies. Papers reporting only expert opinion or case reports were excluded.
Papers dealing with the natural history of limb length discrepancy as well as studies in which gait analysis was performed in patients with limb length discrepancy were identified. Only 10% of the population has exactly equal lower limb lengths. Approximately 90% of the population has a limb length discrepancy <1.0 cm. Hip and knee pathology is present in an increased number of patients with limb length discrepancies over 5 mm. Hip pathology is more often present in the long leg, knee pathology has been reported in various studies to be more common in either the long or short leg. Low back problems seem to be more common on the short side in patients with limb length discrepancies. A number of different compensatory mechanisms for limb length discrepancy have been identified during gait analysis.
There seems to be a consensus that limb length discrepancies >2.0 cm are frequently a problem. There is some evidence that limb length discrepancies as little as 5 mm can lead to long-term pathology.
小肢体长度差异的长期影响在文献中记载较少。通俗文献中大量提及下腰痛、髋关节病变、膝关节病变和足部问题。医疗保健人员经常建议对结构性和功能性肢体长度差异使用增高鞋垫，然而肢体长度不平等的自然病程以及可能推荐的治疗方法的有效性尚不明确。本文的目的是记录和评估与小肢体长度差异相关的文献。
使用PubMed对英文文献进行检索，以识别论述肢体长度差异影响的论文。仅报告专家意见或病例报告的论文被排除。
识别出了论述肢体长度差异自然病程的论文以及对肢体长度差异患者进行步态分析的研究。只有10%的人群下肢长度完全相等。约90%的人群肢体长度差异<1.0厘米。肢体长度差异超过5毫米的患者中，髋关节和膝关节病变的发生率增加。髋关节病变更多见于长腿，不同研究报告膝关节病变在长腿或短腿中更为常见。在肢体长度差异患者中，下背部问题似乎在短侧更为常见。在步态分析中已识别出多种针对肢体长度差异的不同代偿机制。
似乎存在一种共识，即肢体长度差异>2.0厘米常常是个问题。有一些证据表明，小至5毫米的肢体长度差异也可能导致长期病变。
