Effect of Anterior Cruciate Ligament Injury of the Knee on Bone Mineral Density of the Spine and Affected Lower Extremity: A Prospective One-Year Follow-Up Study

Abstract

The objective of this 1-year prospective follow-up study was to assess, with dual-energy X-ray absorptiometry (DXA), the effect of an anterior cruciate ligament (ACL) injury of the knee on areal bone mineral density (BMD) of the injured extremity and lumbar spine in two separate patient groups: 21 surgically treated patients (group A) and 12 conservatively treated patients (group B). Clinical and functional status of the patients and BMD of the spine (L2-L4), dominant distal radius, femoral neck, trochanter area of the femur, distal femur, patella, proximal tibia, and calcaneus of both lower extremities were determined at the time of the injury and after 4, 8, and 12 months. A surgically treated, complete ACL rupture (group A) resulted in considerable and statistically significant bone loss to the affected knee (distal femur 21%, patella 17%, proximal tibia 14%; P < 0.001 in each), whereas the other sites were clearly less affected. Patients with a conservatively treated, complete or partial ACL injury (group B) had only a small but statistically significant bone loss at the patella (-3%; P = 0.005) and proximal tibia (-2%; P = 0.022) of the injured knee, and the other sites remained unchanged. The obvious differences between the groups A and B in the severity of the injury itself (complete or partial tear), its treatment (surgical or conservative), and subsequent rehabilitation (longer nonweight-bearing times in group A) explain these different BMD results, and the forthcoming years will show whether the considerable posttraumatic osteoporosis in the affected knee of group A patients will finally recover, and if so, to what extent.

Alendronate prevents bone loss and improves tendon‐to‐bone repair strength in a canine model

“…8,9 Bone loss following tendon or ligament injury has been noted at a number of insertion sites, including the flexor tendon, the rotator cuff, the Achilles tendon, and the anterior cruciate ligament. 8,[10][11][12][13] These results suggest that bone resorption is an important factor contributing to the accrual of repair site strength. They correlate well with findings that, following tendon-bone repair, bone loss can lead to widening of the osseous repair tunnel, preventing establishment of a strong tendon-bone interface.…”

Sclerostin Antibody Treatment Enhances Rotator Cuff Tendon-to-Bone Healing in an Animal Model

“…Rotator cuff tears are associated with loss of bone at the healing interface and a lack of regeneration of the functionally graded, mineralized fibrocartilage found in the healthy attachment 4 . Bone loss has been observed at healing tendon-to-bone interfaces at multiple anatomic sites [5][6][7][8][9][10][11] . The loss of mineralized tissue is likely caused by mechanical unloading during the period from tearing through surgical repair and by high osteoclast activity during the healing period after repair 10,12 .…”

Fratura supracondiliana do fêmur durante salto após reconstrução artroscópica do ligamento cruzado anterior

“…Adicionalmente, ruptura do LCA tratada cirurgicamente implica considerável perda óssea mineral no joelho afetado, principalmente na região distal do fêmur. Podem ser citados pelo menos três fatores que influenciam tal ocorrência: o trauma por si só, aumentando ní-veis hormonais responsáveis pelo direcionamento mineral; o próprio procedimento cirúrgico, que interfere na estrutura óssea; e a possível imobilização pós-traumática, levando ao desuso do membro (12) . O protocolo de reabilitação aplicado pela equipe responsável no presente estudo respeita o tempo fisiológico necessário para cicatrização do enxerto.…”