What is the cause of paraspinal tenderness post-operatively?

From the Guidelines

Paraspinal tenderness after surgery should be managed with a multimodal approach, prioritizing non-opioid analgesia, such as COX-2 selective inhibitors or conventional NSAIDs, combined with paracetamol, as recommended by the PROSPECT guidelines 1. The management of paraspinal tenderness after surgery involves a combination of pharmacological and non-pharmacological interventions.

• Non-opioid analgesia, including COX-2 selective inhibitors or conventional NSAIDs, is recommended as the first line of treatment, with paracetamol as a baseline treatment for all pain intensities, as it decreases supplementary analgesic requirements 1.
• For high-intensity pain, COX-2 selective inhibitors or conventional NSAIDs, combined with intravenous strong opioids by patient-controlled analgesia (PCA) or regular injection, are recommended 1.
• Muscle relaxants, such as cyclobenzaprine or methocarbamol, can be used to reduce muscle spasms contributing to the tenderness, although their use is not specifically addressed in the provided guideline.
• Gentle stretching and progressive movement as tolerated can help prevent stiffness and promote healing, while ice and heat therapy can be applied to reduce pain and inflammation. The tenderness occurs because surgical manipulation disrupts muscle and soft tissue around the spine, causing inflammation and protective muscle spasms.
• Most paraspinal tenderness improves within 2-4 weeks post-surgery, but it is essential to contact the surgeon if you experience worsening pain, new neurological symptoms, fever, drainage from the incision, or if pain persists beyond 4-6 weeks.
• The PROSPECT guidelines recommend a procedure-specific approach to analgesia after total hip replacement, which can be applied to other surgical procedures, including those involving the spine 1.

From the Research

Paraspinal Tenderness after Surgery

• Paraspinal muscles are commonly affected during spine surgery, and paraspinal muscle atrophy (PMA) is a potential complication after lumbar spine surgery 2.
• A study found that there was a significantly higher mean postoperative volumetric PMA with fusion vs nonfusion procedures, with posterior fusion vs anterior fusion, and with conventional fusions vs minimally invasive (MIS) fusions 2.
• The amount of postoperative PMA was evaluated in different types of lumbar spine surgery, including lumbar fusion vs nonfusion procedures, posterior lumbar fusion vs anterior lumbar fusion, and MIS posterior lumbar decompression and/or fusion vs non-MIS equivalent procedures 2.
• Another study found that paraspinous muscle area correlates with psoas muscle area, and larger paraspinous muscle area is associated with lower mortality rates after surgery, suggesting that the paraspinous muscle may be an alternative to the psoas muscle in the context of objective measures of risk stratification 3.
• However, there is limited evidence on the management of paraspinal tenderness after surgery, and most studies focus on the prevention and treatment of postoperative pain in general, rather than specifically addressing paraspinal tenderness 4, 5, 6.

Management of Postoperative Pain

• The American Pain Society, with input from the American Society of Anesthesiologists, commissioned an interdisciplinary expert panel to develop a clinical practice guideline to promote evidence-based, effective, and safer postoperative pain management in children and adults 6.
• The guideline recommends the use of multimodal regimens in many situations, although the exact components of effective multimodal care will vary depending on the patient, setting, and surgical procedure involved 6.
• The panel found that evidence supports the use of different pharmacological and nonpharmacological modalities, including acetaminophen and ibuprofen, although the efficacy of these medications may vary depending on the specific pain condition and patient population 4, 5.

Predictors of Surgical Outcome

• Previous studies have shown that the psoas muscle is a significant predictor of postoperative outcomes, and paraspinous muscle area may be an alternative measure of risk assessment 3.
• The measurements of paraspinous muscle area at T12 were normally distributed, and there was a strong correlation between paraspinous muscle area at T12 and total psoas area at L4 3.
• Paraspinous muscle area was significantly associated with 1-y mortality in both females and males, suggesting that larger paraspinous muscle area is associated with lower mortality rates after surgery 3.