**Background:** Musculoskeletal disorders (MSDs) are a leading cause of disability worldwide, with low back pain (#1), neck pain (#6), and other MSDs (#7) among the top conditions contributing to years lived with disability. While numerous factors affect MSD causation and prognosis, the potential role of indoor environmental quality—given that people spend approximately 90% of their time indoors—has been under-researched. This systematic review aimed to assess the relationship between eight categories of healthy building determinants (HBDs) and extremity and general MSDs, building on a companion review that examined HBDs and spinal MSDs.
**Methods:** The review followed PRISMA guidelines and was registered with PROSPERO (CRD42022314832). Four databases (PubMed, CINAHL, Embase, PEDRo) were searched from inception through April 15, 2022. Eligible studies included original human research in English on adults ≥18 years, examining at least one of eight HBD categories (air quality and ventilation, dust and pests, lighting and views, moisture, noise, safety and security, thermal health, water quality) in relation to extremity or general MSDs. Two authors independently screened studies, extracted data, and assessed study quality using the NIH quality assessment tool (14 items; scores: 0-4 poor, 5-9 fair, 10-14 good). Evidence levels were categorized using Oxford Centre for Evidence-Based Medicine criteria. Empirical evidence statements were synthesized across 33 pairwise comparisons (3 MSD regions × 11 HBD categories/sub-categories).
**Key Results:** Fifty-three studies with 178,532 participants were included. Most studies (35/53) assessed workers in occupational settings; 14 assessed general populations. Study quality was good in 8 studies, fair in 43, and poor in 2. Evidence levels were predominantly level 4 (39 cross-sectional studies), with 7 level 2 prospective cohorts and 6 level 3 case-control studies; no level 1 studies were found. For upper extremity MSDs, weak evidence supported positive relationships (poor HBDs associated with increased MSD risk) for 9 HBD categories: air quality and ventilation (e.g., OR 1.43, 95% CI 1.06-1.94 for wrist/hand pain with poor air circulation), dust and pests, moisture, noise, safety and security, thermal health (cold, uncomfortable), water quality, and overall work environment. Conflicting evidence was found for lighting and views and thermal health (warm). For lower extremity MSDs, weak evidence supported positive relationships for moisture and thermal health (cold, warm, uncomfortable), but weak evidence suggested inverse relationships for lighting and views and water quality. Conflicting evidence was found for air quality and ventilation, dust and pests, and noise. For general MSDs, weak evidence supported positive relationships for air quality and ventilation, noise, safety and security, thermal health (cold), water quality, and overall work environment. Notably, exposure to cold work environments showed strong and consistent associations across multiple studies: cold-exposed workers had significantly greater prevalence of shoulder pain (PR 3.84, 95% CI 1.61-9.17), hip/thigh pain (PR 13.44, 95% CI 1.66-108.9), and general MSK symptoms (OR 11.96, 95% CI 6.12-23.45). Poor air quality was associated with increased MSD risk in multiple studies (e.g., OR 2.45, 95% CI 1.97-3.03 for temperature complaints and UE MSDs).
**Clinical Implications:** The findings suggest that suboptimal indoor environmental conditions—particularly cold temperatures, poor air quality, and uncomfortable thermal environments—are associated with increased risk of extremity and general MSDs. While the evidence is predominantly from lower-level observational studies precluding causal conclusions, the consistency of findings across diverse populations and settings supports the plausibility of HBD-MSD relationships. Clinicians managing MSDs should consider inquiring about patients' indoor environmental exposures as potential contributing factors. For policymakers and building stakeholders, these findings provide preliminary evidence that investments in healthy building features (e.g., improved ventilation, thermal comfort, noise reduction) may have downstream benefits for musculoskeletal health. However, the authors caution that no controlled trials exist to confirm that HBD interventions improve MSD outcomes, and the field requires higher-quality research including randomized controlled trials, health economic evaluations, and studies examining the rising trend of working from home.