Researchers used a musculoskeletal model to predict joint contact forces and investigate the variations of joint contact forces due to joint impairment in 18 juvenile idiopathic arthritis patients.

Erica Montefiori et al. Linking Joint Impairment and Gait Biomechanics in Patients with Juvenile Idiopathic Arthritis. Annals of Biomedical Engineering 2019; 47(11): 2155-2167

KEY POINTS: JOINT IMPAIRMENT & GAIT BIOMECHANICS IN JUVENILE IDIOPATHIC ARTHRITIS

• Juvenile idiopathic arthritis (JIA) is the commonest rheumatic condition in childhood, although the etiology remains unknown.
• JIA encompasses several subgroups but most generally presents as peripheral arthritis.
  • Clinical presentation includes fever, joint swelling and pain, hepatomegaly, lymphadenopathy, cardiac involvement, splenomegaly, and skin rashes.
• Medical imaging of JIA:
  • Ultrasound is used to assess joint synovial and tendon inflammation.
  • MRI helps with...

This small study of healthy volunteers explored differences in the coronal biomechanics of the trunk, pelvis, hip, and knee joints, as well as gluteus medius muscle activity during walking and step down tasks.

Komsak Sinsurin, Raul Valldecabres & Jim Richards (2020) An exploration of the differences in hip strength, gluteus medius activity, and trunk, pelvis, and lower-limb biomechanics during different functional tasks, International Biomechanics, 7:1, 35-43, DOI: 10.1080/23335432.2020.1728381

KEY POINTS: BIOMECHANICS OF FUNCTIONAL TASKS

• Functional impairment of glute med can lead to excessive lateral trunk bending, which is often observed in people with knee problems.
• During gait, the following was observed:
  • Increased contralateral pelvic drop and pelvic obliquity excursion, compared to step-down tasks.
  • Increased lateral bending versus step-down tasks.
  • Significantly greater knee adduction, compared to step-down tasks.
  • Peak hip...

Although this is a small study, the paper contributes to our knowledge base around the gait variations that are seen in people with chronic obstructive pulmonary disease.

Wai-Yan Liu, Kenneth Meijer, Jeannet Delbressine, Paul Willems, Emiel Wouters, and Martijn Spruit. "Effects of Pulmonary Rehabilitation on Gait Characteristics in Patients with COPD." Journal of Clinical Medicine 8, no. 4 (2019), 459. doi:10.3390/jcm8040459.

"Subjects with COPD walked with less consistent organization of movement patterns of the lower extremities across walking speeds. These findings suggest the presence of neuromuscular deterioration in the locomotor system, reflecting less healthy movement patterns in subjects with COPD.”¹ (p.2).

The authors comment on the role of biomechanical joint limitations, as well as other factors in the discussion, section (and they do a good job of acknowledging the study’s limitations).

ANATOMY REVIEW...

The subtalar joint is a complex articulation that is often overlooked clinically, frequently ignored in favour of talocrural and midfoot mobility. But understanding the anatomy and mechanics of this joint can allow for better movement retraining through the foot, knee, hip, pelvis, and lumbar spine.

ANATOMY REVIEW: THE SUBTALAR JOINT

• The subtalar joint (STJ) is formed by the talocalcaneal (TC) and talocalcaneonavicular (TCN) articulations.
• These 2 articulations have separate synovial sheaths. However, they don’t move independently and therefore function as a single joint —> allowing motion of the hindfoot in relation to the talus.
• Anterior STJ = TCN articulation; middle STJ = interosseus tunnel (canalis + sinus tarsi); posterior STJ = TC articulation.
• Ligamentous support is integral to the integrity of the subtalar joint, with no muscular attachments onto the talus.
  

^{Ligaments of the subtalar joint, originally published by Iosiah Weitbrecht,...}