NMES and Orthopaedic Surgery: Why Recovery Begins Before Surgery

Neuromuscular electrical stimulation (NMES) is often associated with postoperative rehabilitation. However, growing evidence suggests that introducing NMES before surgery can play a meaningful role in improving patient outcomes (Punnoose et al., 2023; Walls et al., 2010; Patanè et al., 2025).

This approach is based on a simple principle: the patient’s muscular status at the time of surgery influences postoperative recovery (Gillis et al., 2022; Hiyama et al., 2026). In other words, better preoperative muscle function is generally associated with better functional outcomes after surgery (Punnoose et al., 2023; Devasenapathy et al., 2019). This concept, often summarized as Better In, Better Out, is now supported by robust evidence across several orthopedic settings (Gillis et al., 2022; Jørgensen et al., 2024).

Preoperative Muscle Strength: A Modifiable Prognostic Factor

Among the many factors that influence recovery after orthopedic surgery, preoperative muscle strength stands out for two reasons. It is strongly associated with postoperative outcomes (Devasenapathy et al., 2019; Takamura et al., 2024; Hiyama et al., 2026), and it can be improved before surgery (Punnoose et al., 2023; Walls et al., 2010).

Total Knee Arthroplasty

In patients undergoing total knee arthroplasty, preoperative quadriceps strength is one of the strongest predictors of postoperative function (Devasenapathy et al., 2019; Hiyama et al., 2026). Patients with greater strength before surgery are more likely to achieve satisfactory mobility and functional recovery.

Several studies have identified strength thresholds that predict walking ability six months after surgery (Takamura et al., 2024). More recently, Hiyama and colleagues (2026) reported that patients who regain age-adjusted normative quadriceps strength experience greater satisfaction and better functional outcomes one year after surgery.

Anterior Cruciate Ligament Reconstruction

A similar pattern is seen after anterior cruciate ligament reconstruction. Significant preoperative quadriceps weakness is associated with poorer knee function one year after surgery (Kim et al., 2022). Conversely, patients with greater preoperative strength tend to achieve better functional outcomes. These findings are consistent with the conclusions of a recent systematic review (Qiu et al., 2020).

Shoulder Surgery

Preoperative muscle strength also plays an important role in shoulder surgery. In patients undergoing anatomic or reverse shoulder arthroplasty, abduction and external rotation strength are among the strongest predictors of postoperative function (Hao et al., 2022a; Hao et al., 2022b).

Grip strength, often considered a global indicator of muscle health and sarcopenia, has also been associated with outcomes following shoulder arthroplasty (Lee et al., 2023). More recent evidence suggests that it may also predict functional recovery after rotator cuff repair.

NMES: An Opportunity Before Surgery

If muscle strength affects postoperative outcomes, an obvious question arises: can this factor be optimized before surgery?

NMES represents an attractive option, particularly for patients with pain, marked weakness, or functional limitations that restrict conventional exercise.

In a pilot study involving patients awaiting total knee arthroplasty, a home-based NMES program increased quadriceps strength by approximately 28% before surgery (Walls et al., 2010). These gains translated into faster recovery of strength and function in the early postoperative period, while also limiting muscle atrophy.

These findings align with the broader evidence supporting prehabilitation. A meta-analysis published in JAMA Network Open, which included 48 randomized controlled trials and more than 3,500 participants, found that preoperative interventions significantly improved muscle strength and physical function before surgery. Benefits persisted during the first weeks of postoperative recovery (Punnoose et al., 2023).

The Role of NMES After Surgery

NMES remains a valuable tool after surgery.

During the early postoperative period, muscle recovery is limited by pain, joint effusion, immobilization, arthrogenic muscle inhibition, and reduced physical activity. In this context, NMES can effectively stimulate muscle activation despite these limitations.

Following Knee Surgery

After arthroplasty or ligament reconstruction, rapid quadriceps weakness represents a major clinical challenge. Early use of NMES may help attenuate strength loss and accelerate functional recovery, particularly when voluntary activation remains impaired.

Following Shoulder Surgery

Although evidence of preoperative NMES in shoulder surgery remains limited, postoperative findings are encouraging. Recent studies have shown that NMES may reduce deltoid atrophy after rotator cuff repair and accelerate recovery of abduction strength (Yoon et al., 2026).

Other studies have reported earlier improvements in external rotation strength when NMES is applied to the infraspinatus during the initial phases of rehabilitation (Reinold et al., 2008).

Sarcopenia: An Often Overlooked Factor

Beyond muscle strength, preoperative muscle mass also appears to influence outcomes.

A meta-analysis including more than 14,000 patients found that low preoperative muscle mass was associated with a significantly higher risk of major postoperative complications and short-term mortality (Weerink et al., 2020). In total knee arthroplasty, low muscle mass has also been identified as an independent risk factor for postoperative blood transfusion (Hwang et al., 2022).

These findings highlight that preoperative preparation is not solely aimed at improving function. It may also help reduce surgical risk.

Key Takeaways

Current evidence points to a consistent conclusion: preoperative muscle status has a direct impact on recovery following orthopedic surgery.

For rehabilitation professionals, this represents an opportunity to intervene before the operation takes place. NMES appears particularly valuable for optimizing a modifiable prognostic factor, especially when pain or functional limitations prevent patients from performing high-intensity strengthening exercises.

From this perspective, the period leading up to surgery should no longer be viewed as passively waiting. Instead, it should be considered a therapeutic window during which clinicians can improve a patient’s muscle reserve, support postoperative recovery, and ultimately enhance functional outcomes.

In orthopedic rehabilitation, recovery often begins long before the patient enters the operating room.

References

Bodkin, S. G., Norte, G. E., & Hart, J. M. (2019). Corticospinal excitability can discriminate quadriceps strength indicative of knee function after ACL-reconstruction. Scandinavian Journal of Medicine & Science in Sports, 29(5), 716–724.

Devasenapathy, N., Maddison, R., Malhotra, R., Zodepy, S., & Sharma, S. (2019). Preoperative quadriceps muscle strength and functional ability predict performance-based outcomes 6 months after total knee arthroplasty: A systematic review. Physical Therapy, 99(1), 46–61.

Gillis, C., Ljungqvist, O., & Carli, F. (2022). Prehabilitation, enhanced recovery after surgery, or both? A narrative review. British Journal of Anaesthesia, 128(3), 434–448.

Hao, K. A., Wright, T. W., Schoch, B. S., Struk, A. M., King, J. J., & Farmer, K. W. (2022a). Association between preoperative shoulder strength and clinical outcomes after primary reverse total shoulder arthroplasty. Journal of the American Academy of Orthopaedic Surgeons, 30(15), e1035–e1044.

Hao, K. A., Wright, T. W., Dean, E. W., Struk, A. M., & King, J. J. (2022b). Preoperative shoulder strength is associated with postoperative primary anatomic total shoulder arthroplasty outcomes and improvement. Journal of Shoulder and Elbow Surgery, 31(8), 1648–1656.

Hauger, A. V., Reiman, M. P., Bjordal, J. M., Sheets, C., Ledbetter, L., & Goode, A. P. (2018). Neuromuscular electrical stimulation is effective in strengthening the quadriceps muscle after anterior cruciate ligament surgery. Knee Surgery, Sports Traumatology, Arthroscopy, 26(2), 399–410.

Hiyama, Y., Sawa, R., Yokoyama, M., & Ishii, Y. (2026). Achieving normative quadriceps strength after total knee arthroplasty: Associations with satisfaction, function, and a predictive nomogram. The Bone & Joint Journal, 108-B(1), 45–52.

Hwang, D., Han, H. S., Lee, M. C., & Ro, D. H. (2022). Low muscle mass is an independent risk factor for postoperative blood transfusion in total knee arthroplasty: A retrospective, propensity score-matched cohort study. BMC Geriatrics, 22(1), Article 137.

Jenssen, K. K., Lundgreen, K., Madsen, J. E., Kvakestad, R., & Dimmen, S. (2018). Prognostic factors for functional outcome after rotator cuff repair: A prospective cohort study with 2-year follow-up. The American Journal of Sports Medicine, 46(14), 3504–3510.

Jørgensen, S. L., Aagaard, P., Bohn, M. B., Mikkelsen, L. R., & Mechlenburg, I. (2024). The effect of blood flow restriction exercise prior to total knee arthroplasty on postoperative physical function, lower limb strength and patient-reported outcomes: A randomized controlled trial. Scandinavian Journal of Medicine & Science in Sports, 34(1), e14516.

Kim, D. K., Park, G., Wang, J. H., Kuo, L. T., & Park, W. H. (2022). Preoperative quadriceps muscle strength deficit severity predicts knee function one year after anterior cruciate ligament reconstruction. Scientific Reports, 12(1), Article 11845.

Lee, B. G., Lee, D., & Koh, J. H. (2023). Relationship between the preoperative grip strength and postoperative shoulder strength of patients treated via reverse shoulder arthroplasty. Journal of Shoulder and Elbow Surgery, 32(5), 1012–1019.

Patanè, P., Carnevale Pellino, V., Febbi, M., Gatti, R., & Sirtori, V. (2025). Effects of a tele-prehabilitation program with indirect electrostimulation compared to home-based exercise in patients eligible for lower limb arthroplasty: A randomized controlled trial. Journal of Clinical Medicine, 14(3), Article 892.

Punnoose, A., Claydon-Mueller, L. S., Weiss, O., Zhang, J., Maffulli, N., & Rushton, A. (2023).

Takamura, D., Iwata, K., Yajima, Y., et al. (2024). Cut-off values of preoperative knee extensor strength and hip abductor strength for predicting good walking ability after total knee arthroplasty. Archives of Orthopaedic and Trauma Surgery, 144(1), 305–312.

Walls, R. J., McHugh, G., O'Gorman, D. J., Moyna, N. M., & O'Byrne, J. M. (2010). Effects of preoperative neuromuscular electrical stimulation on quadriceps strength and functional recovery in total knee arthroplasty: A pilot study. BMC Musculoskeletal Disorders, 11, 119.