An ankle sprain occurs when ligaments, the fibrous bands connecting ankle bones, are stretched beyond their limits or torn. The injury triggers an acute inflammatory response characterized by swelling, bruising, and sharp pain. While this initial phase is intense, many find the most confusing part of recovery is when the pain seems to worsen or spike again toward the end of the first week. This increase in discomfort, often around the seven- to ten-day mark, signals a distinct transition in the biological healing process. Understanding the physiological and mechanical factors at play clarifies why this temporary setback is often a normal part of recovery.
The Body’s Subacute Pain Response
The initial acute phase of healing, marked by inflammation, typically lasts for about six to seven days. As this initial swelling and chemical irritation begin to subside, the body shifts into the proliferative or subacute phase, which is dedicated to repairing the damaged ligament tissue. This repair work is complex and involves the recruitment of specialized cells called fibroblasts to the injury site.
Fibroblasts deposit new, immature Type III collagen, creating a provisional scaffold for the new ligament tissue. This tissue is structurally weak and disorganized, making the ankle vulnerable to stress. The increased cellular activity and the formation of this fragile repair matrix can cause a noticeable resurgence of aching or throbbing pain as the joint is stressed by even minimal movement.
This period of repair is also accompanied by nerve sensitization, known as hyperalgesia, where nerves become overly sensitive. Even after the bulk of the inflammation fades, the localized pain receptors around the torn ligaments remain highly reactive to pressure and movement. This heightened sensitivity means that normal, gentle movements which were not painful days earlier may now register as intense pain, contributing to the feeling that the injury is regressing rather than improving.
Common Reasons for Late-Stage Pain Spikes
While the biological repair process is a major contributor to the pain spike, behavioral and mechanical factors compound the issue. The initial reduction in swelling during the first week can create a false sense of security, prompting a premature increase in activity. Many people begin walking more or stop using their crutches sooner because the ankle looks and feels less swollen.
Resuming near-normal activity often exceeds the functional capacity of the weak collagen scaffold, leading to mechanical overload and increased pain. Even minor actions, such as standing for too long or walking on slightly uneven ground, can re-aggravate the healing tissues that are not yet strong enough to handle full weight-bearing loads. Furthermore, removing support too soon, like discarding a protective brace or wearing footwear that offers insufficient stability, leaves the joint unprotected during this vulnerable repair phase.
The “weekend warrior” effect is another common cause for a pain flare-up around this time. If a person rests adequately during the work week but then attempts a higher level of activity over the weekend, the sudden increase in demand stresses the healing ligament. This cycle of overexertion followed by inflammation and pain is a signal that the weight-bearing tolerance of the ankle has been exceeded.
Warning Signs of a More Serious Injury
While a pain spike in the second week is often a sign of normal healing, there are specific symptoms that signal a complication or a more severe injury that needs professional medical attention. An inability to bear any weight on the injured foot after the first five to seven days is a significant red flag. If the pain is localized directly over a bone, especially the bony knobs on either side of the ankle (malleoli) or the base of the fifth metatarsal, it suggests a possible fracture that may have been missed in the initial assessment.
Persistent numbness or tingling in the foot or toes should be evaluated promptly, as this indicates nerve involvement or irritation. The feeling of the ankle “giving out” or being chronically unstable is another serious sign, potentially indicating a complete ligament rupture. Unlike the deep ache of a healing ligament, sharp, stabbing pain with specific movements or a dramatic increase in swelling that resists elevation indicates potential re-injury or a serious underlying issue, such as cartilage damage.
Transitioning from Rest to Active Recovery
As the body transitions into the subacute phase, the management approach must also evolve beyond the initial period of strict rest. The traditional RICE protocol gives way to a more dynamic approach encouraging controlled movement. The goal is to stimulate healing and restore function without causing mechanical re-injury.
Gentle, pain-free range-of-motion exercises should be introduced to prevent stiffness and promote blood flow to the area. A common starting point is the “ankle alphabet,” where the individual traces the letters with their big toe. Once this is tolerated, a gradual introduction of exercises to rebuild strength and balance, known as proprioception, is necessary.
This often involves the use of resistance bands for controlled strengthening of the muscles surrounding the ankle. Physical therapy plays a considerable role at this stage, guiding the progression from gentle movements to single-leg balance work, ensuring the ligament heals with sufficient strength and stability to prevent future sprains.